A few of the bars have letters next to the name. I have personally witnessed extra services performed on customers sat in these bars :) H = Hand, B = Blow.
In my opinion the Soi offers the best 'A Go Go' bars in Bangkok. My personal favourites are Tilac, Spice Girls, Cowboy 2, and Dollhouse - and I know the Asian visitors love Baccara. Don't forget Soi Cowboy is within spitting distance of the Asoke BTS station / Sukhumvit MRT station. So its very easy to get to.