After extensive testing, these tires are not for me.
357446
I ran these tires in 28" and 30". I had them for almost 2 years. I typically do alot of hill climbing with boulders, rock ledges, and some dirt. I am not a mudder, I drive around any mud hole I see. I liked these tires for a long time but I had nothing to compare them to to make my judgement. While I had the tires I liked them and thought they were pretty good. As more and more friends got SxS's I was able to draw more a comparison as we would climb hills and I would get to watch first hand and on video what tires worked and which ones didnt. I have wheeled these tires on granite, sandstone (Moab), and limestone.

Size: These tires ran true to height. These tires do not run true to width. The 10" wide tires are about the same width as a 9" wide stock tire. The contact patch is ballooned and not very flat. About the only thing that comes in contact with the ground is the centers of the tires.

Where these tires shine: The asphalt, or anything high speed. The only time I had gotton a flat with these tires was when I ran over some metal that put a hole in them, purely my fault. They never let me down on the trail. These tires are pretty stiff, to get them to half way bit on the rocks I needed 8-9 psi. But if you wanted to blast around at full speed you needed 12-13 to keep them from rolling over in the corners. So you had to pick your poison on tire pressure. They get the job done on pure rock hill climbing (Moab) but they are definitely not the best tire for it. I felt I was breaking more parts because of the wheel speed these tires need to climb with. Your coming in on the floor and when they finally do get a bite it was causing parts to break. A tire that hooks up will require alot less skinny pedal.

Where these tires don't: Anywhere there is loose dirt or mud on steep hills. If you are trying to climb a  steep hill that is wet forget it, you're on a slip and slide. I decided to hang these tires up after watching a friend come to a complete stop in the middle of a hill and then hammer down and climb to the top. I had to come in hot at it and barely climbed it and I tried multiple times, while sliding all over the hill like it was made of ice.
400431
I'm not into racing anymore either, but I got a set of the GP Attack and Force tires for relatively cheap, both were $79, so at that price I had to try them to see what I was missing after years of not using racing tires.  I found out I wasn't missing anything but money!!

These GP Attack and Force tires are normally very expensive at around $120 for the pair, and they only lasted 1,600 miles before they were completely bald, I had forgotten just how fast racing tires wear.  On top of that they wore out together which meant I had to buy a pair of tires instead of just one like I would normally.  You see with normal road tires the rear will wear out first, then I move the front that would still have roughly 50% of it tread left, and move it to the rear, then buy just one new tire and put it on the front (you should always have your best tire on the front for safety reasons in the event of a blowout going around a curve for example).  With these GP's that can't be done.

They also turned out to be rather flat prone, in those 1600 miles I had roughly 14 flats, and the tires got cut up easily so I had to apply about 8 tire boots to seal up cuts that went completely through the tire, and fill up with Superglue about 20 cuts that if left untouched would have lead to even more flats.

I also didn't not think they rolled any better then other tires.  And for a person to declare they felt the difference is lying, unless they has a wattage meter to compare the differences between one set of tires and the GP Attack and Force their never going to feel it unless they were rolling on cheap Walmart tires previously.

Handling wise they were pretty good, better then cheap tires, but no better then average priced road tires.  They were however smoother riding due to the thin sidewalls, which also means the sidewalls are more prone to damage then most other tires, but most of the Continental line of tires the sidewalls are fragile.

I have a problem spending $120 retail for tires that will only last 1600 miles or so at a cost of $13 per mile...that's FAR more then you would spend driving a car including gas and wear and tear!!!  Unless you have so much money that you just don't care what you spend on tires, or riding your bike in an actual race, then avoid these for recreational, fitness or training rides.
600641
Didn't work for the size of bike tires I need so I returned it.
2965485
Way less rolling resistance than Stock mountain tires
4839780
Unboxed, and all tubes had issues. Odd bulges, ruptures upon inflation, etc. I have ridden on conti tubes and tires for years and love them. But these seem like factory defective that were resold in bulk. I won't buy these again, back to boxes and vendors I am familiar with
4938705
I guess they look like what they are supposed to look like. The "slick" tred in the center of the tire feels very thin. I'm not sure I trust it to be very durable or puncture resistant, but we will see. I really hope I can get through a season without wearing a hole in these tires.
101765
I typically use my bicycle to get around rather than my car, so my tires accrue a fair number of miles over a couple of months. I tried to be thrifty and save money buying these tires instead of something by continental, panaracer, or michelin, each of which typically run 5 to 10 bucks more. Bad idea, one of the tires failed very quickly and I found them more difficult than usual to get onto my rim (I was using the 27 x 1.25 size). I found these tires to be a constant frustration. Fast forward to my purchase of Panaracer Paselas ($30 ea.) for one of my bikes, and "Michelin City Mountain Bike Tire with Protek" for my 700c sized bike -- haven't had a flat in over a year. I'll give the Vittoria Zaffiro's a 2 because they're cheap, and one of them didn't suck.
535829
I essentially purchased these tires because they were relatively cheap, they had decent reviews about their "silkworm technology", rolling resistance, and the orange matched my frame. I doubt I have ridden more than 300 miles on them and have had at around 4 or 5 flats. I do live near a college campus, so I can't deny there isn't hidden glass in parking lots and the roads. Despite this, I have had flats when riding back home where the streets are good quality and there is no street litter. I have been fairly disappointed with these tires. At least they didn't cost me too much.
1645958
Not quite sure why others have had good things to say about these tires. They are beautiful, and they do hug the road really well. However, I am returning my set after one week. I ride about 200 miles a week, and the previous tires (Continental) took me for almost a year without a single flat tire. I have been out on these tires three times with two flat tires. So.... buy these if you either don't plan on riding on a road, or you really want to practice changing tires.
1784106
These tires are sticky! I didn't believe it at first but your fingers stick to the rubber a little. The rubber material is harder than the Alias tires on the Rustler.
143966
Purchased 6 of these, 4 for two road bikes with 2 for spares. After less than 500 miles on relatively smooth surfaced roads the 700x32 rear tire on my Trek hybrid developed a bulge in the tread area about 1/4" high and 3" long with a very noticeable distortion in the tread. Obviously it thumped quite badly which is how I discovered it. After changing it I could not find any separation of the casing inside the tire, just a weak area that you could push out easily with your finger. These tires are serviced correctly prior to each ride with the maximum rated psi (87). Could just be an isolated incident but now I am questioning the safety of these as I ride 100% by myself out in rural areas.
4212655
Been running these tires for a few months now on an older atv. Supreme traction. No punctures or flats yet. At the recommended 4lbs they do ride incredibly stiff and rough, however, I believe that is a result of the bias ply construction. To fix this I simply air down until they are comfortable. If I had to do it again, I might have gone for the maxxis bighorn where you're paying for a much more comfortable ride.
504196
I was really impressed by the tire for the first two seasons of riding on them, they were comfortable, rolled well, high mileage capability and had great traction dry or wet, but start of the third season I found a problem.  I own quite a few bikes and none get ridden exclusively, they all get ridden which means they are stored when not riding and those stay inflated, and all of them of course have tires and they are all in fine shape even after 5 years, I even have the original set of Silver Star Mark II tires that came on a 84 Fuji when it was new and those are in fine shape as well after many years of being stored deflated (in case you're wondering why I never rode on them is because I swapped them for Specialized Turbo tires.  So why did I bring those tires up in a review about Hutchinson Intensive 2 Hardskin tires?  Because after just 2 years and about 2,000 miles (they are not even close to being worn out) those Hutchinsons are the only tire I've ever owned where the rubber, the tread, has long cracks in it.  I've never had a tire crack like that, not even tires that are 33 to 34 years old, not even cheaper Panaracer Stratus Sport tires that cost $24 new.  So I rated these tire with just 1 star because the cracking destroyed my lasting impressions of them, this cracking is unacceptable, it's detrimental to the longevity of the tires for anyone who buys them.
2629165
I was delighted to put these tires on my bike in 2012.  I thought that they'd be the ultimate long-lasting tire, what with the reinforcing metallic threads they contain.  Unfortunately, that feature turned out to be their Achilles heal.

After yesterday's ride, the rear tire lost most of its air.  After patching the tiny hole in the tube, I felt the inside of the tire to see if I could discover if whatever I'd run over was still stuck in the tire.  What I found though wasn't any road debris -- it was a tiny piece of metallic thread that was protruding ever so slightly on the inside of the tire.  By shedding a lot of light on it and getting out a magnifying glass, I was able to determine with certainty that the tiny bit of metal wire was actually part of the tire!

The total number of miles I rode on this tire was a measly 723.  After having previous "normal" mountain bike tires last for thousands of miles, this is an unacceptably low lifetime for the tire.  Luckily, I had an old tire -- one with 2500 miles on it -- that I could use for a replacement, at least temporarily.

Now I'm just waiting for the second shoe to drop -- the inevitable failure of the front tire.  I certainly will not be buying any more tires with this innovative design, nor will I be recommending them to anyone.  I strongly urge even the most casual riders to reconsider if they're thinking of purchasing any of these tires.  Though their design at first glance seems to be a good one that will protect you against them failing, they're actually a very poor value and you will end up replacing them sooner rather than later.  Do not buy these tires.
4050469
I'm having a lot of problems with this tire (700C x 25mm) and rim.  First problem has been the tight fit on my Velocity A23 OC 700C rim with a tube. Velocity has told me that their A23 rims run a little large in diameter to accommodate tubeless tires.  But they post that the A23 rim is OK for a 'clincher' setup.  Anyway, I've concluded that this rim and tire are not a good match - when using tubes.  When you have a very tight tire fit - you need to exert a lot of force with your tire levers (I use Topeak) to get a bite on the bead to begin removing.  This makes is easy to add another tube puncture.  And likewise installation is more difficult. You can catch the rim tape and move it - exposing sharp spoke holes. I realize it may not be fair to blame the tire manufacturer alone since the rim and tire function together as a system.

But since this tire fits so tight to the rim - choice of rim tape will be critical - the 16mm Velox cloth tape just didn't work for me with the tire/rim. Even with very thin rim tape - I still have problems seating the tire evenly on the rim bead.  After inflation - part of the tire sidewall will remain in the rim center well (the low, center area of the rim).  Continental has a video cautioning about checking for this problem on their website.  After inflation  - I need to remember to visually check how the tire is sitting on the bead - I've had some success removing some air and pulling the tire sidewall up by hand.  In an effort to try to get the bead to seat evenly - I have a tendency to over-inflate the tire.

What I've learned is don't shrug off a tight fitting tire as just a minor nuisance - it will make it a big task to repair.  Anyway, I've put maybe 100+ miles on this tire over the last year riding year round in the Denver area (with a lot of road sand in the winter months) - I'm unhappy with this tire/wheel.  I'm running this tire on the rear and have had 3 flats and no flats on my new front tire (different brand).  I'm 200+ lbs in weight - maybe that is the difference - I'm putting much more weight on this rear tire.  So puncture resistance has not been anything exceptional - and I know that if I have a flat  - I expect to spend a lot of time getting back on the road with a TON of frustration.
4193129
Bought 4 tires that were  out of round causing shaking in the rear end and in the front.
3126884
I bought a set of these tires for my lexus had an aligment done before I got the tires mounted on my rims, drove like a normal human being no hooning around and the tires only lasted for 13,000 miles that is with 5000 mile rotations as well. I called ohtsu and they told me the alignment specs I had were not what they consider reasonable for my car and would not warranty the tires. Please save your money and buy different tires.