Pros: -Good performance, easy to solder and since the leads are soldered upon receipt,easy to verify correct wiring! Although I replace the tiny leads with 22 ga. teflon stranded wire. I guess I have used at least 2 dozen in 3 X and 4 X "D" alkaline cell maglite mods driving one Cree XR-E Q5 per board in groups or 3 or 4 LEDs on a 5/16" (8 mm) round disk, snug fit, Artic silvered heatsink with no problems. However.......

Cons: When I try to drive the same Q5s over 6 volts with these boards (ie. 5 or 6 "D" cells alkaline power) with the same set up and heatsink I am getting 1 of 3 or 1 or 4 board burnout rate! As I said, these boards have performed 100% at 6 volts and under and since they are rated for 9 volts, I should expect the same reliability in a 5 or 6 "D" alkaline maglite mod as a 3 or 4 "D" use. Anyone else have a problem at higher voltages? Can anyone suggest a more robust board?

Other Thoughts: I suppose I could use a power resistor to limit incoming volts, but since the main advantage of the 5 or 6 cell configuration is increased run time (aside from the ability of the flashlight to function as a club... a definite plus for my security oriented customers) I would really like to use all the power the big "D"s have to offer!

Bottomline: Well performing board for 6 volt and under applications. I will continue to order and use these boards for their reasonable and LED friendly (800ma) output,dependability and ease of use. However their weakness in handling voltages above 6 volts has both embarrassed me and cost me money and lost respect from my customers and friends.

Pros: 1. Great price
2. Build quality is good enough
3. Very compact
4. Does what it is made for: to drive a LED with constant current instead of constant voltage + resistor (draw your batteries empty and save money instead of throwing them away half full)

Cons: 1. Output current not adjustable
2. Very thin leads
3. No documentation (however, not difficult to find)

Other Thoughts: I unsoldered R1 (0,02 ohms) and soldered a 0,1 ohm resistor instead of it. A tricky thing to do but it worked. Why? To reduce current to about 200 milli-amps and save battery power. I used it with a Cree P4 on a modified bike light. Enough light!!

Bottomline: Great value for money. Why not offer a board with an empty R1 space?

Pros: cheap, easy to use, fit various installation position well (i used it for flash light and table light, still experimenting it with counter top light). It works well with SKU 1445 (SSC P4 Z-LED).

Cons: order took so long (more than two months). Solding jobs on those SMDs are pretty poor. However the circuit is so simple, with such poor workmanship, it still works well.

Other Thoughts:

Bottomline: If you don't mind long waiting and working device even though the workmanship is poor, this is pretty good deal. Especially good for experiments. Saw couple comments talking about no open protection, i haven't gotten chance to verify it whether it would blow out the LED or not.

Pros: Exactly what i was looking for,
great for custom builds /upgrades
Does exactly what it says on the tin give or take a few percent (they do not come in a tin but all clattering about in deal extremes lovely red "don't panic" bubble wrap)

Cons: none! nada! zip! zero! zilch! not one! okay maybe one... flimsy wires but they'll do :p

Other Thoughts: Should be wrapped individually to stop clattering about whilst in transit from china land :)

Bottomline: buy it, build it, save yourself some $$$$