$13 is a STEAL of a deal! I have messed around with all of the Chinese line of the NovaTac lights. I'll just list the pro's and cons.
PRO'S
- four levels of light
- smaller package than the HDS
- emitter swaps are very easy using 14mm boards
- steps down when battery depletes
- lexan lens won't break (but does scratch)
CON
- some of them develop a flicker at sub-lumen levels
- the positive spring is too soft and "head end" battery changes cause the spring to deform
- lexan lens does scratch easily
The easiest way to minimize the CON list.
I used a piece of #6 solid copper to replace the positive spring, keep ALL contact points extra clean and if the lexan bothers you when it's scratched swap it with borafloat. The PRO's vastly outweigh the CON's on this light.
Swapping an XM-L on a 14mm board into this light transforms it easily from 120 lumens into 260-ish lumens, trust me, I have done at least 6 swaps on the Storm, Classic and Special Ops.