If you are staying at TST, you could try Hari's. But personally I find the atmosphere there very quiet and uncomfortable.
Near the same area is Sticky Fingers. Live Rock-n-Roll bands and usually can pull some talent out of there. And lots of SW around if you just stand outside for 5 mins. They will come running up to you.
But maybe save that for day 3.
For your first time I recommend catching the MTR to wan chai. Walk around some of the bars over there. Not the flashy velvet curtains bars, but neptunes II, Makati, Escape, Traffik.
You can chat up a nice girl, have some drinks, and then pull a nice WG for an overnighter.
Check out Tony Toro's full write up:
http://forum.sex141.com/eforum/v ... light=%2B%2Btoro%2B
Then on day 2
You have to try a TST HG. Call the papsan for an appt after having your top 5 list handy.
Either get a local HK number (more convenient for call backs) or you can call from your computer using skype.
I dont think you would be able or up for walk up service on your first trip unless you are a seasoned mongerer from other countries/places.
I personally have never been to k-pressure or 37dundas so I can not comment on those.