Having finally visited HP for the first time, below are my observations (mostly consistent with comments in this thread and club reviews).
To be clear, I find both clubs to offer enjoyable and pleasant experiences, so no comments should be misinterpreted as being negative on one club vs another. It's merely a matter of preference of girls/women and club layout/decor.
I can see myself frequenting both clubs, based on my mood/goal on a given day.
1 - Younger (much younger) girls/women at HP
2 - Tip parade at HP is certainly real, but as others noted, its impact is largely driven by number of girls on stage. When there were 6 girls on stage, it was a bit much, but I maintain my stance that you generally won't spend much more under the HP tip walk scenario than if you were stage-side at a more traditional club. I acknowdge, though, that PLs tipping habits vary greatly, so YMMV.
I was pleasantly surprised to see that the tip walk consisted solely of a quick handover of $1, then she's on to the next PL. At some tip walk clubs, it's "one for the other tit? One for the kitty?" nonsense....not here. I even saw one guy tell a girl "I'm waiting for {dancer name}, and she moved on without a fuss after he didn't tip her.
I actually believe you may end up tipping more at PL, due to tendency of women at PL to do some barside dancing.
3 - HP is a bit more modern and clean than PL. For some reason, I was expecting a dive bar, but HP is actually quite nice.
4 - HP is VERY small. Just a long and narrow space, with minimal distance between walls and bar/stateside seating.
5 - Due to smaller space, HP feels a bit cramped when there are many guys there. PL seems to offer a bit more space between PLs.
6 - Dances at HP are a bit more robotic than PL, with girls being a bit less playful and flirtatious/enticing. I attribute it to the demographic of the dancers. Of course, both clubs will have both cold and flirtatious dancers...it just seems that HP girls are more stiff.
7 - HP LD booths are a bit small vs PL, which have spacious LD rooms.
8 - More BBLs at HP.
My preference? Playhouse Lounge, due to older dancers being a bit more flirtatious, and larger LD booths. But, I will continue to visit both.