Good walking around lens but not perfect.
594164
Love the ability to go from 18 to 200 in one lens. It definitely has sweet spots however. It would be improved if it had an auto stabilizer feature. Overall a good walking around lens for most applications when you don't want to change lenses frequently.
3621914
I bought it knowing it would be a very situational lens. It's good for the price when compared to the higher quality lenses of this type.
16506
pro's 1) You don't need to constantly change lenses.
  2) images  are tack sharp
  3) image stabilization works well
con,s 1) autofocus goes hunting at critical times
  2) lens is heavy
  3) some vignetting at 500.
4) somewhat stiff when going from 50 mm up.
5) exposure metering is also problematic and I often have to go off my eye.
I bought this lens because I mainly shoot scenic and wildlife photography with doing  minor work in sports, friend's weddings etc. I shoot with  Canon 5-D Mark 3 which is a tremendous camera. I would find myself hiking carrying my canon 100-400 , a wide angle, and have an all around lens on the camera and sometimes a doubler and tripod. That is alot of equiptment and weight and alot of lens changes. Often shooting wild life, by the time you change your lens the animal is gone and even with modern day sensor cleaning you are risking getting dust and debris in the camera. A friend of mine who has a Nikon turned me onto this lens which he really liked. There was the obvious convenience of not changing lenses or having to carry so many.
I went up to Glacier Park to try it out. With my Canon lenses I shoot with the 61 point autofocus. I almost never have a focusing issue. I focus hold the shutter down then frame the picture however I see fit. This lense does not like 61 point autofocus.  So I chose other auto focus options and I thought I found one that it seemed to like. That is until I found 3 bears cubs mom sent up a tree. Being very quiet sure enough The kids descended one by one. My focus had been perfect, then right when the photo was perfect the lens went hunting, totally out of focus. I had to nix the autofocus and manually focus. I got one semi-usable  image.
This happened so frequently esp with complex background that I went to manual focus.

addendum: I have changed the metering to single point autofocus only, I shot a horseshow today with show jumping. The lens  performed reasonable well with few out of focus images.
Note this lens does an excellent job with scenics, but that wasn't what I bought it for. I will have to see how well this change does with wildlife in complex backgrounds.
Also note due to the high f stop use of a doubler whether with this lens or Canon lenses  is going to drop the lens 2 stops and you have to manually focus.
1557863
At about 1/8 of the price of the similar lens made by Sony, this lens is a good substiture.  There is some slight blurring on the very corners of the screen, but most of the blurring is beyond the viewable region for most TV's so it's barely noticable.  It doesn't work with the still photo mode on my HDR-SR1 but I use the still mode so rarely that it doesn't matter to me.
2361663
The lens is a great lens. I use it for indoor photography thanks to the wide aperture (small F-number). It gives pretty good bokeh. It doesn't compare to a good 50 mm lens for bokeh, though; nor does it compare to a good 24 mm lens for up-close portrait and action snapshots. It's in the middle, and it'll do a good job, though. The lens is very quiet thanks to the SWM (Silent Wave Motor). One main drawback is that the lens is missing Vibration Reduction (VR), so the lens's low-light benefits are less effective if your hands aren't steady.

The tripod doesn't stand a chance. I took it to the beach and one of the feet balls got lost in the sand. I also lost the mount piece, so it is useless to me now. Prepare yourself to buy another tripod in the near future.

The filters are great! I've had no issues with them. The only cleaning product I got was the squeeze poofer thing, if I remember correctly. I didn't get the rest of the cleaning supplies. Maybe I did, but I don't remember using them or seeing them.
2435288
This is by far my favorite lens. It's excellent for walk around. At 100mm you do find yourself having to step back quite often. But if you like closeups then this lens seems like an almost must have. I had borrowed one for a few weeks and I was very sad to give it up so I ended up getting one for myself. So glad I did.

Being limited to 100mm makes me look at things differently and is slowly making me a better photographer.
988486
It is very handy to switch from scenes to macro, easy twist on and off while walking around.  I like the shots I'm getting. But the connectors are goofy. The adapter fits very snugly. It is stuck on my X VARIO PZ 14-42mm. Not tragic, because the lens cap does fit over it and I only have one lens like that but not ideal. The lens fits loosely on the adapter. If you continue to rotate it, it comes off (in either direction) and it did fall off once.
2261723
Good lens for the money. Everything on this lens is great except one thing: it's a bit slow to focus. Compared to my Canon 70-105mm lens, this thing is really slow with the autofocus.
1182574
So it took a little deliberation when rating this lens and deciding between 4 stars or 5 stars but after some thought I came to the best conclusion i could. Now at this point obviously i settled on 5 stars and while this lens is by no means flawless it is still perfect.

Lets go ahead and start with the Pros.
- Fast usable zoom while it's pretty apparent that this lens is a 2.8 it is a little surprising how well it performs at 2.8 the shots while not razer sharp are still exceptional and completely usable images and its holds its own and beats the much more expensive and 20 year old canon equivalent.
- Macro capability not exactly a "true" macro but a nice feature none the less with the ability to capture some pretty nice shots.
- Decent build while i probably would feel safe fending off a wolf or bear with this lens I still think it is built well and certainly feels much better than even well built plastic lenses.
- AF the actual ability to focus is good outdoors and reasonable indoors on my 7d with only slight hunting in lower light.
- Lens collar I'll come back to the collar itself but i will give it points for including a collar with the lens at no extra charge.
- Smooth zoom and focus rings both of which feel well built and durable.

Now here are my only Complaints
- AF this is not a USM equivalent and you have to understand that the motor is efficient but it is not anything close to quiet even when it appears to have focus it will still buzz for a second or two.
- Lens collar so while i appreciate the thought for me this collar is not going to get much use. I am 6'8" with very large hands and I'm in a position that i get to choose between a usable zoom ring and the collar so no collar for me but your millage may vary.
- AF-MF so I'm not sure what they were thinking when they designed the focus on this thing but the implementation of switching from auto to manual is somthing I'm trying to get used to with its push pull thing. I will say that when it works properly its pretty fast but it's disappointing that they didn't put in full time override and at least with my lens about half the time when throwing it into manual it gets stuck half way.

So those are the good the bad and the kind of ugly ideas Tamron had when creating this lens. Now to the conclusion i came to this is the perfect lens because it does things that matter well and the other stuff is merely a matter of convenience not necessity. It's the only (the sigma has horendious IQ wide open and therefore doesn't deserve a 2.8 rating) alternative to a 1000+ dollar IS version 2.8 and therefore it is the best.
2241323
Otherwise this lens is merely good.  I've had this lens for a little over a year and have taken numerous rolls on it in all kinds of settings and conditions.  It does what it promises to, which is to provide a nice wide-to-medium telephoto focal range (suitable for 99% of casual photography) with the fast ring type Ultra Sonic Motor autofocus.  It also lets you focus manually even if the switch is on AF, which is really slick.  If it weren't for these features I might not have given it a 4 because the optics are just not that good.  It's not very sharp at any focal length, and it produces duller colors than the other 2 lenses I have.
But like I said, the lens performs as it's meant to - as a better than entry level consumer grade lens.  The USM is so fast that it justifies the lens's optical shortcomings.  Your subject simply *pops* into focus instantaneously when you start to depress the shutter.  I'm about to move on to a sharper and more "contrasty" lens, but it'll be heavier, bigger and won't focus as fast.  The time that I did spend with this lens produced some very nice results and it served its purpose quite well as a solid stepping stone in my continuing education as a photographer.
1828159
This is a pretty nice lens but I don't feel like it zooms enough or is sharp enough to be very useful for shooting moving or skittish animals / objects.

It's hard to get close enough to fill the frame with the subject and I found the focus very soft at bigger apertures.
1618373
This lens is mostly great.  It's small, light, excellent zoom range, and combined with a camera that has reasonably good low-light performance is a good "I'm going on vacation and don't want to bother with equipment" type lens.

[I've used the lens with a Canon 7D, and have encountered no issues with the combination]

I've taken about 2000 photos with it since purchasing it about 2 months ago.  And the results have mostly very good.  Keeping in mind that my intent was to have a small lens that could take my vacation snapshots.  For that situation, I really want something that consistently focuses pictures, that has effective anti-shake capabilities.

So I used this indoors, outdoors, with almost no light, in broad daylight, in caves, pretty much everywhere.  Here are my observations:

1) In general, the lens handled nicely.  As you zoom in/out, the lens is not as smooth as more expensive lenses (not a big deal), however, the zoom mechanism is like a telescope and as it engages the next "section" you have to get past a "notch".  This is a bit of trouble if you're shooting movies with it as you cannot do a smooth zoom.  For still pictures, it is not an issue

2) The anti-shake works pretty well.  I hand-held shots in caves and they mostly came out very sharp.

3) In broad daylight, you get mostly in-focus shots, however, as I went through my pictures, there were times when taking pictures in broad daylight that were out of focus.  Not consistently, but about 5-10 out of 500 where you think "How could the lens mess that up?".  I don't have an answer for why; I have to conclude the focus is slow

4) Its a light lens.  Good thing, the 7D is very heavy

5) At the ends of the zoom ranges, the pictures are dead on in terms distortion.  In between, there are a few oddities.  I frankly don't care about that.  I'll use a different lens for those times.

6) I used it at races in bright sunlight, and I was able to get consistently sharp pictures of motorcycles traveling at extremely high rates of speed.

Overall I like it because it take pretty good pictures, great zoom range, light, and inexpensive enough that I'm not worried about the lens being damaged.

I considered the Canon in the same zoom range, but based on reviews, this lens is similar in performance and is about $250 cheaper.  That's significant in this price range.
2304639
Good lense for the price, noisy when it tries to autofocus. i should have gone with newer version of this lense
3815760
It is a nice lens for the price. sometimes it is hard to get out of the Macro mode, switch sticks. There is a lot of focusing back and forth, wish that would be easier. You could easily miss a nice shot because of it. Other than that, I like the lens.
3636487
I've had this lens for a few years, having used it on a Nex-7 and then the A6000. It's pretty good, especially if you restrict the zoom to no longer than about 150 (which is over 200mm on the 35 format). Photos are fairly sharp, good color, good contrast, though I do pretty much always sharpen them and increase contrast afterwards. Pushing the lens up to 210 can give you some fairly soft images, depending on how far away your subject is, and it doesn't do particularly well in low light. The super lightweight nature of the lens is possibly it's biggest advantage--this thing is incredibly light and compact for what you get.

I'm heading to Havana (probably once in a lifetime trip) in a couple of months, and I'm troubling over whether to bring the A7 w 24-70 Zeiss and Sony 70-200 (super sharp!) on the A6000, or leave the 70-200 behind for this one. I can get good images from the 55-210 if I follow the above rules (and still have the same reach as the 70-200), with half the weight of the better lens. But the 70-200 is...sharp as razor blades, and I won't be able to reshoot these images,...so it's convenience vs. aesthetics. I'll be walking miles and miles each day, so weight is crucial, but it'll be miles and miles through Havana.... Ah, sweet First World worries....
4638627
The reason I bought this lens was because of its silence motor for video shooting. I needed one for my 7D Mark2 as my other wide angle option is either the heavy 24-70mm F2.8L, 18-55mm II, or 10-22mm. The zoom range of 18-135mm is a good complement to my 55-250mm STM. With these two lenses, my focal range is pretty much covered for video. Because of this reason, I didn't have a high hope for still photography as I know this lens has some compromises on its optical performance. Nevertheless, I use it for still occasionally. Having been spoiled with some of the awesome L lenses notably the 70-200mm F2.8L II and 16-35mm F4L II, I felt the 18-135mm was not that sharp. However, as long as you are not pixel peeping, it does its job as a decent walkaround lens. I also felt that my other 28-135mm was a tad sharper but unfortunately it does not go as wide as the 18-135 and the image stablization of the 28-135mm is quite outdated. The 18-135 is almost complete silent when its image stablization and AF kick in. These are the main selling points.

I didn't purchase this lens from Amazon. In fact, I bought it from Canon online refurbished store to save a few bucks. It 's just as good as new. It 's a shame the lens doesn't come with a hood like other third party lenses like Sigma or Tamron. Even my Sony E mount lenses come with a hood. So I don't quite understand this Canon policy for consumer lenses. If you don't need STM motor for video, I would suggest looking elsewhere. Sigma has made some really good lenses recently. For roughly the same price, you get more value from Sigma or Tamron. For these reasons, I give the 18-135mm a three star rating.
3421116
This is a VG lens, and a good value if purchased used.  It's a bit heavy but that's from the 2.8 ability.  The lens hood notching to fit to the lens body needs a little work in the design.  It does not always go on correctly and it is possible to put it back on the lens reversed and to miss fitting the notch/threads correctly.  There is strong vignetting apparent from 2.8.  If you are shooting in high contrast and open sky, you will see the vignetting all the way from 2.8 to 5.6.  That's a little disappointing but it's not visible/apparent below 2.8 unless you really look for it.  If I am going to walk around with this lens I zoom it back in to 24mm.  The reason for this is that fully extended the lenses internals do make a slight noise as you walk, like some parts of the lens are pressing against the internals.  This lens is pretty sharp for a zoom.  Clearly a solid deal/alternative if you don't want to pay the high price of the Nikon equivelant.