I am a fan of the four floors of hoes a.k.a. OT a.k.a Orchard Towers.
Doesn't really start until after 9 every night.
I use the freelancers bar in the first floor. About $150 should get you a gal for a LT at your hotel.
I've never bothered with Geylang or Sammy. I just catch a cab to OT, walk around the bar, pick and walk out...can take as little as 15 minutes to see before you buy.
Enjoy.
BS