There is a fair bit of intel on Singapore in this post:
http://forum.sex141.com/eforum/v ... &extra=page%3D1
I love both Ipanema & BRIX.
You get more Vietnamese and a few others at Ipanema, BRIX tends to be a little more global - girls from many countries. Prices are higher at BRIX, quality depends on what you value. I took a super hot Viet from Ipanema that would have been the best looking girl at either bar (IMO), so it really depends on what you like. I would highly suggest checking both out for yourself and seeing what you like.
I've gone to both bars in the same night on more than one occasion - they are easily within walking distance.