I voted for Casey Daugherty, Kim Perez, and Vikki Gates.
But I'd also say that Sheilahe Brown is criminally underrated. Her upper body is the equal of anyone, and her biceps are phenomenal.
Star Blaylock is stunningly beautiful. I think she's retired, though.
As far as the top competitors go, I was surprised to see the lack of Betty Viana fans on this site. For my money she's easily the sexiest woman in the upper echelons of the sport.