Without hesitation Inari Vachs! She's so underrated that it should be a crime why she never blew up like some other girls (Jenna Haze comes immediately to mind, ugh!).
I would definately have to go with Heather Brooke from Ideepthroat.com, the things she can do are simply amazing... if only I could meet a girl like her
Btw, ANY of her scenes are awesome. lol Maybe that's just my opinion, but I find all of them great. Look for her in blowjob series like Blowjob Fantasies and Dr. Fellatio.