I have heard that there is no mistaking the MP. It is really tough and can not be broken apart. Now the P&B with whatever it picks up will be soft and breakable in my opinion, so they should be easy to tell apart. I have done lots of P&B shakes and only got out what I put in. I would love to see some MP but nothing yet, not even questionable. I don't know either but I wouldn't waste my money on formulas when you can get the same thing from local stores at a fraction of the price.