Beam width adjustment is very useful.
936882
Even brighter than I thought it would be. Beam width adjustment is very useful.
2311199
They work great and brighten things up. I wish they were easier to adjust the angle of the beam of light. To change the beam direction up and down you need to loosen 4 bolts and then tighten them in place.
4590642
Sturdy, design and placement of triple lamp with separate controls makes for a very useful office tool. Lighting adjustments add to the scenic moods that envelope a room.
1045086
The beam is bright and I get decent battery life out of it.  It is a bit narrow of a beam compared to others, but that's not really a downside to me.  It is easy to accidentally bump the light button if you have it in a pocket or bag, and once or twice I've pulled it out to a dead battery because of this.  Overall, I'm happy with it.
1091294
Great focused beam. Beam is round with 1 spot and not rectangular due to the expected beam pattern of a row of leds ( so optics was optimized for the beam pattern ).
Tint is good like tint of Rigids. Build is great too.
I recommend it for the price as long as you open it and fix a few quality control issues....
1. Put a lot of thermal compound as it seems to have almost none.
2. Check the screws where the cable / wire attaches to the board. Mine was not as tight as it should. vibration might cause the light to flicker and die.
3. Check the sealing rubber gaskets. if possible add a little silicon grease / gasket maker to help make sure that the gasket seals.
Wish would be the aluminum pcb should be copper and the leds should be mounted on copper as well.
1917957
WOW!! that is all I have to say. This is a great light. Everything is great except one feature. The beam is not adjustable.  If it was adjustable I would probably order more. I am not disappointer at all.
1549625
This is the fourth one. Given them as gifts to my sons. They love the power of the beam. And being able to expa and the beam to cover a wider area. My son uses the vibrating beam feature to show his clients where he is standing when he's on his job. My neighbor and his sons have purchased them.they really likehow brilliant the beam...almost daylight
3432455
Nice construction, very bright light and adjustable.
4575281
Wow!

I first converted my Maglite 4D from incandescent to single LED -- and that was OK, but the beam was too narrow.  This time I converted to the three LED Terralux -- and it is much, much, better.  My 4D uses four rechargeable NiMH D-cells.  The light beam pattern of the Terralux is like a flood light, but with a long reach.  I can light up a half acre long and wide pretty good with the Terralux.  The light color is warm, like in the 4300K region.  The three reflectors seem to be precision-made, and that is what sets this light above the rest.  The beam pattern has substantial depth with enough breadth.  Also, there is a dip switch for choosing between selectable and always high -- I set mine to always high.  I use my 4D to do the nightly 5-mile dog walk along some dark roads and parks.
3044660
I haven't fully tested it yet, but I like the brightness, the accessories, and adjustability.  In particular the illumination pattern when zoomed out wide, which is wide and evenly lit.

Not the most comfortable, but I haven't fully adjusted it yet.

Perhaps a little heavy, at least compared to the cheap plastic products.  But this is so much better,  it's worth the extra weight.
3717303
Seems to work well.  Casts a bright beam and should prove useful in emergency situations.
2728393
My first impression of this light is being surprised at how compact it is, roughly 1 3/4 " diameter and about 2" long not counting the mounting bracket. Very bright light but according to the LED manufacturer the maximum output is 1040 lumens which is still substantial. My main complaint is how narrow the
 main beam is- a small, very bright center that abrupty transitions to a wide, faint circle. The fix is probably to retrofit one of the wide-angle lenses available here but in the meantime I'm using an older LED light that is wide angle but lacks distance in conjunction with the new light. I just received the light yesterday and haven't had a chance to test the battery pack to determine runtime.

The silicone rubber band does a decent job holding the light on handlebars but the pressure needed to press the power button can rotate the light downward a bit; I'll probably end up devising a sturdier means of holding it in place.
4072477
At certain times of the year it is dark when I leave for work and dark when I get home and I have inadequate outdoor lighting. This was my quick fix and it works great. I like that the angle of the beam is adjustable vertically.  Bought another one for my emergency kit.
4048520
Great light adjustable beam easily removed as a flashlight. anchprs well to handle bars.  Fast shipping alsoI probably will get another for my other bike.
2085331
I've had these for a few weeks now. I like that the temples can be adjusted longer/shorter and this fits over my glasses, although not really comfortably. But the glasses do the job - enhancing how well you can see the red laser line especially when there are other competing light sources. I've tried this in bright outdoors where the difference is not big enough to help, but indoors it makes a noticeable difference.
360955
I like the battery gauge and auto dim based on motion. Well constructured. Quite a wide beam, good for narrow single track. I also have an MK5 that I really like as well.
4517318
As noted in the title for this review, I received the 5W version, and it seems very adequate in brightness for some night-time driving, though only just so.  If you're looking for a version of these that will be up to that task, I wouldn't suggest selecting any weaker-powered models.

I really like the tail-light's strobe mode, which really will grab the attention of a driver behind you, though I don't see much use for the strobe-setting on the front light, as that will probably make you so dizzy you'll wreck.  The high-beam/low-beam option for the front light is nice as well.

The beam width adjustment is a nice touch:  the width of the beam is very easily adjusted with the telescoping body.  In the useful range, it appears that the beam width ratio is roughly 1:1.  In other words, at 30 feet away, the beam's about 30 feet wide; at 15 feet about 15 feet wide; etc.  One can easily adjust the width and direction of the beam to cover the entire road at about 30-40 feet ahead of you, and one can adjust the width of the beam to fit the speed at which you're riding, where the useful width might vary.

I also like the ease of installation on both lights, though the tail-light has me a bit worried with its nearly all-plastic mount.  The only metal part of the attachment is one screw (another screw is plastic, as is the entire ratchet mechanism).  The mounting apparatus for the front light is almost all plastic as well, but it is sturdier.

The all-metal construction of the lights' bodies is impressive, as is their weather-sealing.  These look very well made and should last a long time.

A convenience is the rechargeable Li battery in the main light, chargeable via included USB charger.  It would have been nicer, though probably not as size and cost-effective, if the rear light ran on rechargeable batteries as well.  Speaking of size and cost, it would have been simple, though perhaps more expensive, to make this main light smaller and brighter.  I have a much brighter tactical LED flashlight that's about this same size, though it costs about twice as much.  It all depends on what you're looking to save on -- space or cash.

All in all, a nice kit, though, and I'd definitely recommend it.