I can recall one dancer and one porn star. Both were during the first few years that I started visiting clubs and before I got good at figuring out which dancers were worth a bit of extra effort.
The first and one I to this day regret not taking the chance on was a very hot looking 9.5 brunette. Perfect natural tits, nice firm butt. She danced at the club for about a year and a half. She had just started dancing and gave a very good stage show, but seemed very aloof and full of herself the few times I talked to her. She asked me twice if I wanted a dance and both times I said no. I rarely saw her get any dances, except for three regular customers who would come in once every so often. I found out about a year after she quit that she was entertaining the customers outside the club, and if you got a lap dance from her more than likely she would mention some OTC action. The club didn't care as long as she gave a good tip out.
Second was on vacation vising a club where well known at the time porn star happened to be featuring. After her first show I went to the back for a polaroid and I was the only one in line. The club was dead so she offered a video, photo and 3 song private show for the same price as the 3 song special. So I agreed. Very good dance, lots of contact and a bit of extras. At the end of the dance she offered a private session at her place after her 1:30 AM show for a very reasonable price. Problem was by the time she had gotten cleaned up after her show I would have been at her place around 3:00 AM, and I had to leave for home at 5:00 the next day. She retired soon after.