If you use these powders, I think one big aspect of what you choose is that it be naturally sweetened or non-sweetened versus containing something like acesulfame or sucralose, etc. IMO, that can be as important as if it's isolate or bulk protein powder. Most are straight up overpriced and if you have a natural food store or a discount health food store near you, you can sometimes get it for considerably less. A health food store near me sells a mixed concentrate / isolate whey protein powder in bulk for $12/pound that seems to be the equivalent of what you'd pay $20 or more for in the plastic tubs. Most of that stuff is still an artificially sweetened mess that my GI reacts to so I don't use the sweetened ones if just for that reason. YMMV.