Vietnam for travel, PPenh for pussy.
Out if all the different girls I've done I find the Cambodians the nicest that I've enjoyed my time with, if you are a nice guy (without being a noob) you'll be treated well and meet some Nice girls.
In HCMC it's tough taking anything back to your hotel and you are looking at $100 minimum for anything decent. A lot of the Hot Toc shops near the airport have closed down and the best you'll get at the others are bj's and some need a few visits before they'll do this. You are an atm to the Viet chicks, but they are gorgeous.