I would have to say no, since you'd have to be pretty bold to use it without a critical burst, plus it's unsafe on block, unlike the power blow which causes guard break
I want to say yay, just because accidentally doing a PL has fucked me over a few times when lag has kicked in just as I was about to do an input, but I'm going to say nay. Hazard's comment explains my feelings towards it.
I think your presumption is correct. But you have to either land a CB or bait a hold to extend a stun to land one. It's not like it's just free damage.
True that. Plus you have to actually put in relatively much effort to get your damage. compared to regular combos due to needing a better timing. Although people have invented no-timing PL combos, some of them are actually not that easy to perform.