As for the Surefire, you'll note I'm not sold on one yet. Again speaking completely candidly I don't need another light. In fact I could lose/destroy several lights before I'd get to the point of "needing" another light. (shh, don't tell Mrs. TS I said that)
The next light I get will be small. The Coleman and the TK-35 are very bright (900 lumens on the TK-35 on high and I think something like 700 for the CT-70). However, both are medium/big. I'd like something small like the TK-10, something that uses say 2 CR-123s or a single 18650. Finally, I'll be looking for at least 500 lumens, preferably 1000 or more as technology improves. Until this thread came up I hadn't checked-in on flashlight tech in a little while. I see Fenix has several lights that meet those specs right now. Hmm, when I get my tax refund... Wait, didn't I say I don't *need* another light? ;-)
You realize with this discussion you may have gotten someone to change their mind based on an internet discussion... When does that ever happen?
Unless you threw it out, send in the TK-10 for repair or replacement.
Flashlights that accept both 18650 “AND” CR-123s are nice.
What do you use the light for, and how are you on headlamps?