The bags Costco have been selling, the EAS stuff, has been good. Three different types of protein, not just the primary (whey). A good amino acid profile. Add some liquid egg whites for an even more complete supp. I don't usually gain much on protein shakes because they seem to be so much more poorly metabolized than food.
But this stuff has been good to me. Still try to get almost all my protein from food, but that is next to impossible to do and get enough to support growth.
If you have to use a supp, and need a good solid one with a broad profile, get that bag if they still have them. I'd have to spend waaaay more to get something of equal quality from a typical source.