It's probably all gross. I hated soy protein for a long time. I would say to start drinking vanilla soy milk. After you get used to that and like the taste, then you can mix vanilla soy protein with your vanilla soy milk and it tastes almost the same except thicker.
Over the last 10 years of trying to get down to my ideal weight (with 4 kids in between) I have tried them all. Seriously, I would hold my nose and choke down my shakes.