I mostly just use protein powder. It's just extra food and I don't expect any magical things from it. So the only thing I really care about is mixibility, taste, and digestion. Hands down the best I have ever used is AtLarge Nutrition's Chocolate Nitean. The stuff is so yummy that I look for excuses to mix one up.
The worst one I've tried is WalMart's Body Fortress Whey protein powder. It is clumpy, tastes horrible, and gives me gas. I know it's cheap but I don't see how anybody can drink that crap when you could grill up a steak instead.