HVACman:
I'm assuming you're a fitter/technician/engineer and are crawling around voids and having your head stuck in ceilings a lot. I have a very similar job and chose a 6PL about five months ago. Although I have a lot of Surefire lights, the 6PL is the one I carry to work every day.
It's robust and has never ever given the slightest hint that it will do anything other than operate exactly as it should. The beam is a tight white spot with a clean corona with no blemishes. The runtime is ok. Nowhere near what SF claim, but I reckon that 2 x 123s will give you 4 hours plus about ten minutes of fast-fading "emergency" time.
Crucially, the light isn't so strong that it blinds you for close-up work; especially looking at metal or smooth walls. If you are using this for close inspections, I strongly recommend you don't go CPF-crazy and fit an aftermarket 200+ lumen monster drop-in. You'll be seeing stars for days.
All in, it's so simple it's embarassing, yet it looks and feels super-industrial. It's also big enough that it won't get lost, and if you do happen to drop it down a bottomless pit, whilst it's bad news, it's not one of those lights that costs so much that you'll be in mourning for a week.
My guys use Fenix L2ds, and whilst that's ok (and much brighter) the level settings are only a distraction. It's nowhere near as well made as the 6PL and I have already had one report of a unit failing.
Gary