I don't see Bol Bol being like Porz apart from the height, Bol will be more a defensive specialist and if anything will probably be a similar type prospect to Mo Bamba this year.
Bol will be one of the most interesting guys to follow as his sheer size offers a lot of defensive possibilities. Also he looks as if he understands the game well, having a better basketball IQ than a lot of bigs so team mates will be happy to give him the ball away from the paint. Plus he is a good FT shooter which a lot of bigs aren't so sending him to the line won't be a good option.
I like the Michael Redd comparison for RJ personally, it acknowledges his good character and knowledge of the game but I don't see him as a Grant Hill level creative player. RJ with his understanding of the game and his athleticism still looks best current prospect to me.
