This place isn't called rainbow room. It is just in the same building, but on a diferent floor. I have been there place several times and the experiences were nice enough yet not outstanding. The problem is that they do not have the fishbowl concept and only offer 3 to 5 girls (if you're lucky) at a time. After entering the place you change to a Kimono, without taking a shower, then you are led to a room where you can watch silly chinese TV and wait for the girls. They all greet you and then the manager asks you to pick. If you are mean enough to send the first girls away, you will have to wait for a long time for the next girls.
Two months ago, I sent a fellow mpnet member to this place, a guy who visited SH during a business-trip and met me for a pint and some advice. They only presented him 1 girl on a weekday around 9pm, making me loose face completely. After asking for other/more girls, they told him that he would have to wait 40 minutes for anoher girl. He chose the first one, received so-so service and was very disappointed, of course. One hour later he came back to Malones and finally went home with a FL from Manhattan, who provided excellent service by the way.