I know we've had it posted a million times, but
You can use anything you have. The stuff I bought was on sale at the health food store I frequent for $29.99; it's a big jug. It came recommended, so I just hoped it was good, and it was. But everyone has different tastes. I think the peanut butter taste overwhelms the protein aftertaste, because, as I said, even my mom and aunt liked them.