I just bought this product not too long ago. The purpose, for me, is a meal replacement protein shake or a pre-sleep snack/muscle builder. Here is my review: Pros: - Great brand name. ON has established themselves as a well-known and reliable product name. - Reasonably priced. - Taste is GREAT. - Nutrition value is great. - I notice that i feel full when i wake up. Muscles feel good too. Cons: -Clumps slightly when mixing. Honestly not that big of a deal though. Overall i would recommend this product to anyone who is interested in a casein-only protein.