(I could not find a cached copy but my PC still had the contents of my original post of 12/26/10 in this thread, as follows)
My 170T settings:
Preset B [click] (Primary - factory turn-on): low (Level 5, 0.33lm)
Preset C [double-click] (Secondary): medium (Level 16, 15lm)
Preset D [triple-click] (Low): tactical strobe (170lm)
Preset A [press-hold] (High): max (burst level 23, 170lm then steady level 22, 120lm)
Turn On Preset: Enabled, B
Button Lock: Enabled
Automatic Turn Off: Enabled
Locator Flash: Enabled
Momentary: Enabled
Customization: Enabled
I may tweak the exact medium and low levels as I use it more.
Rationale: I always like my lights to come on low first, but with quick access to high. I can't quite do what I want which is click from off to turn on low and press-hold from off to get high; this setup seems as close as I could get, I can get to high via click-press-hold or click, click-press-hold.
I hate memory so must have Turn On Preset enabled.
I probably won't use button lock that much but it doesn't seem to interfere with anything so I'll just leave it on.
Automatic turn off is just for safety in case, I rarely need to run my light continuously for more than 10 minutes, if I do I'll either click it again or just turn this off.
The locator flash is neat to find it in the dark, besides being an "I'm alive" indicator. If the light is on its side the flash can be a bit bright for dark-adapted eyes, but that's why the crenelated bezel is good, put it face-down and you can still see the flashes.
I often only need light briefly so I like momentary.
So far I haven't accidentally changed anything with customization enabled, and it's kind of a hassle to get into customization mode so I'd just as soon leave it on. I did enter it once or twice by accident, but as long as I don't press-hold while in that mode, I won't change anything and it will time out.
It looks like I'm the first one in this thread with every feature enabled. Henry put all those nice features in, gotta use 'em all!
Also, I have both tailcaps, and although I prefer the flat one so it tailstands (a bit wobbly) by itself, it is a bit more difficult to use for me than the regular protruding tailcap - I have to curl my thumb more and it's awkward. Besides, I carry the F04 diffuser with it which makes a fine tailstand.
Update: I went back to the flat tailcap, using a slightly different grip to make it easier to press.