My experiences with KTV are that most of the time after you pick the gal, you regret not picking the one that your pal picked.
I went with a pal to a joint at BJ once and that was exactly what happened. After picking the girl, most of the time I was looking at the girl beside my pal. Somehow about 1hr into the session, an employee came in, turned some funky music on and we could see someone outside keeping watch. The girls all hopped onto our laps and started to bob. The chap started to rap and the girls moved to his rap. At some point they all went topless and obviously we started to grope them. Here's the next surprise. At a command, the girls swapped places. Yes, my gal went to the pal on my left and the one on my right came to me. JUST NICE!!! When the one I liked came to my lap, I took the opportunity to chat with her and told her that I regretted not picking her. Surprisingly enough, she said the same (of course... for more tips). But wait, there's more. I looked at my pal when my gal got rotated to him and he was clearly enjoying himself. So I leaned over and asked him if he liked 'my gal' and he said YES!
He was also hoping that he had picked her. SO viola!! We swapped when the 'show' ended. We switched, brought either back to our rooms for a clearly interesting night.