30DS down on to P90X

AdoraK

I will complete my 30DS this Sunday. I received my P90X DVD's yesterday in the mail and this is what I am moving on to. Question: It recomends having a Protein drink after the workout. I have never purchase or used these before. I know this workout is extream so I am wondering what others that have done the P90X have experienced with and without this protein drink. What proten powder did you use? Any other advice for this workout is welcome.

I am also looking for someone that maybe starting this work out also next week to join me and help motivate each other.