There's a few that could easily pass as female to most of us horny guys, the hard part is having them pass around other women, they seem to be able to sniff out any trickery.
But I'd pick as the most convincing Patricia Araujo. I love Vaniity, not sure if it's cosmetic surgery that's f'd her up a bit or just all the coke dissolving her nose and other drugs she's battled with a la Heather Thomas.
A few post op girls would've been awesome BEFORE they changed like Karol Bonkar and the amazing NY and internet model Naiomi Cruz and her friend Jessica Jourdan.
As for asians, almost any girl that works at Miss Tiffany's cabaret could easily do the job.
But I'll take this one step farther and pick a BOY that just dresses up and looks sexier than most females. First time I saw him perform I thought he looked like Shania Twain. I think it's harder to find a true female impersonator that could pass, and this drag artist, star from Chili is the best I've seen. Under the wig, glued on silicon breasts and marvelous tape job is 100% boy. The fantastic Arianda Sodi....
http://www.youtube.com/watch?v=gXraU9505IA
I'd do her/him any way, any place, any time. LOVE Arianda!!!!!