Flying Turtle
Flashaholic
Hard to say for sure, but it's probably a tie between the CMG Infinity and the Surefire L1.
Geoff
Geoff
Nearly all of my lights have stood up well.
This is going back a ways but I did have a problem with threads giving out on the Nightcutter 2xCR123 lights. They were cool lights for their time with interchangeable heads. I think it was the shortest 2xCR123 light never produced. I still have a few in good working order but I don't use them anymore.