I'm sorry to hear you're having problems with your Surefire lights. I personally don't like some of their business practices, but must admit that only one out of my 10 Surefire lights ever failed to work properly. (A brand new G2 model that came with a blown bulb from the factory). The problem was easily corrected. If your Surefires aren't working properly, give Surefire a phone call. They should be covered under warranty.
Seven of my ten Surefire lights are completely stock. As for the other three, one is a G2 with an older style Novatac clip and a thick O-ring below the tailcap. Another is a Leef-bodied M4. (2x18650 C tail - M head body). I'm running a Surefire MN61 in it. The last is my C2 w/ Malkoff M60 drop-in.
For those times when I need a ton of light, there's my stock Surefire M6.
500 Lumens out the front. Definitely a real torch.