[militarymoron]

TS, basicload answered it better than i could. basically, i didn't find tape switch activation very positive when mounted on the vert grip - sometimes i'd activate it when i didn't want to, and sometimes it wouldn't come on exactly when i wanted it to. i found thumb activation with offset mount, or now at 3 o'clock with the thumb-forward (i'm a lefty) more positive as i was using only the thumb to control the switch on the light, instead of the whole hand. my grip pressure on the vertical remains more constant/consistent. also, with the momentary/click on tailcaps like the SF Scout, you can have constant on if needed, as basicload pointed out.

edited to add: just wanted to reiterate that i'm a civvie shooter for those who don't know me. what works best for me for shooting as a hobby/fun may have no merit in the military world, but just in the offchance it might, i share my limited experience here.