I spent 4-5 days in HCM a few weeks ago and because I am short of time here I will just say DO NOT expect the p4p scene to be as straightforward and accepting as it is in Thailand. I went to HCM mainly for a 'culture visit' and to go on a number of War-related tours and other sightseeing trips. (I recommend the Mekong Delta tour where you cruise back on a a ferry.)
My extent of p4p in HCM was to visit some massage centres which invariably finished with a happy ending. But even then, it was all hush-hush, under the towel and not what you might normally like. The authorities still take a very dim view of this type of tourist service
The girly bars I found to be EXTREMELY pushy. You walk in, they are all over you, and they push very hard for drinks and companionship remuneration. Some have ST rooms upstairs but prices are on the high side compared with here.
Options available on the street - but seemed to be the wrong gender for my liking
Tuk tuk drivers promised to take me here, there and everywhere for beautiful girls, but I'd read some bad stories about this tactic, so politely declined.
Having said all that, I found the girls in HCM to be beautiful, but not as overtly friendly and happy and smiling as in Thailand.
Have a great time whatever you choose to do. But just have your wits about you, because the chances of scam/theft/other nusiance are much higher there.