Pros: It seems to be well built.
Compared to a SmallSun 170 Lumen rated light it seems to be about 10 - 15 % dimmer - so for most ;ights give more Lumens on paper that in the real world, I'd say it's over 100 Lumens anyway.
With 2 * 1.5 Volt primary it's not noticeably brighter, but has increased runtime.

Cons: No cons so far.

Other Thoughts: I use it as a backup light in my car. Maybe I should get some Lithium primaries for longer standbye time.

Bottomline: A good light for almost everywhere avaliable primaries.
Almost EDC size with 1 AAA setup.

Pros: This is a very bright flashlight, and the ability to use one or two batteries is terrific. I like the slender design and keep this handy as one of my personal favorites.

Cons: Threads were not terribly clean, but that was fixed with a cleaning cloth and some mineral oil.

Other Thoughts: I've purchased these as gifts and have had great response. Everyone comments on how bright it is. When giving one as a gift, I write up my own small set of instructions so the person doesn't do something that might break the flashlight.

Bottomline: DX is THE place for flashlights. Keep up the good work!

Pros: The big pro with this torch is the use of AA batteries, available everywhere and cheap enough considering the purposes I consider this torch is best for.
The light output is better than I expected and very useful considering the size of the torch.
I have used both 2x primaries and 2x NIMH rechargeables in this torch and found both worked equally well, however, I am disinclined to leave NIMH in it as I expect they will have self discharged when I do want it to work.
Light output is a fair bit lower when using only one battery, but the torch is then extremely small and still has better light output then most incandescent flashlights.
The build quality is all you could expect (in actual fact it is better than you should expect for the price) and the switch feels OK. I haven't had any issues with the light other then poor electrical connection through the threads when I received it, however, this dissapeared after I had screwed it apart and put it together a few times.

Cons: None really, this light performs extremely well using 2 or 1 AA batteries.

Other Thoughts: I would like to try this with a 3.7v 14500 battery as the extra voltage would potentially brighten it further, not that it really needs it for what I am using it for, however, as the LiPo has very low self discharge it may be a better battery for a light that is left in the car or left on the shelf for a long time before use.

Bottomline: Ideal as a small compact light using AA batteries. I have to admit though that I would give my vote to the X2000 as my first preference for an everyday/car/home shelf light due to it's versatility and flexability.

Pros: :
+ single mode, "no frills" driver
+ versatile powering options
+ bright
+ driver is indeed 4.2V-tolerant (which is not the case for the Q5 equipped sku 10727 with the same body
+ extension tube can be swapped and combined with sku 4452 and sku 10727, which allows operation with 3 NiMH AA cells

Cons: :
- pulls higher current for comparable brightness than the Q5 version (sku 10727), consequently doesn't run that long on the same batteries.

Other Thoughts: Originally purchased to split into extension for me to keep, and the flashlight to pass on, I decided to keep it after the driver of my sku 10727 broke (from using it with 4.2 V) and had to be sent back. It is even brighter than the Q5 model, with the penalty of drawing higher current. This is partially compensated by running it with 3 NiMH 2700 mAh AA cells when I need longer time of operation, or on a single 900 mAh Lithium cell for light and compact form factor, when operational time is not important. The driver runs more efficiently with higher input voltage, resulting in longer operational time, running on a 3.7 V 900 mAh cell, compared to a 1.2 V 2700 mAh cell.

Bottomline: throw cone about 9° (15 cm/m)
flood cone about 84° (135 cm/m)
Output doesn't match a P60 head light, but is quite respectable for its size.