Actually, i made myself one. Got a Lumapower clone host without markings from a friend. used a LCK-LED XM-L on sale at 6usd each and bought a 5 pack of kd 2,8A drivers. Already had the emitter insulator discs and thermal plaster. It was just a matter of well centering the emitter and doing a good job at soldering the driver. Later on fine tuned the reflector with some duct tape to have it sit where i want. It paid off. Very good centering of the xml gave me 38K lux at 1m which is quite good for a XM-L i think. Also it is the only XM-L based flashlight i have that has considerably less spill than expected. The reflector does it's jobe better than anticipated. I used the stock kd wires that came with the drivers. a bit on the short side yes but i managed to use them just fine. The KD 2.8A driver is a son of a "onion" to solder! I have to get a new solderin iron tip which is more pointy than the one i currently have.
Total cost?
Body free (worth max 10usd)
6,15usd emitter
4usd driver
0,2usd disc, solder and goop approx.
total:
less than 11usd without body.
Perfectly doable for 20usd if you can find the body for 9usd or less.
You may want to buy a MRV for 14usd at manafont... (SMO reflector incuded) but beware you have to shop for a 14 or 12mm XM-L star... My version accepted 16mm stars.
I used this torch for my XTAR battery roundup. Used a fan on the body and the flashlight stayed very cool to touch. Wihtout a fan however scorching hot in 10min. I can go for a 70min one shot if i keep it in hand easily without being annoyed from heat. Candle on high is however very unadvised. I forgot it on for 21min on desk and i was amazed how hot it was. I was able to handle it for a few seconds but not much more. I could if life depended on it... but i preferred to not stress myself over nothing.