Both are great GFE.
CA Bambi has slightly larger bone structure than Izzy, more of an athletic body. Not fat by any means, a relatively toned yoga body. She also has one of the better kgirl asses out there. Her GFE is intimate and plenty of kissing. My only knock is that her DFK technique is a little strange, tons of lip sucking, less open mouthed kissing. She will pretty much give her body to you for an hour and be constantly intertwined.
Izzy is more of a classical spinner. Slender, prettier face, but older than Bambi to my eyes. Izzy's GFE is top notch and her DFK technique is better, more open mouthed medium/deep DFK and use of tongue. For me, Bambi wins on body, Izzy wins on face and DFK. But for guys who prefer slender spinners over a more athletic build, Izzy would probably win on body.
I don't think you can go wrong with either girl.