DONT do it. I made this mistake a while back and my Pro Res stuff will not play back properly for some reason- video was jumpy. I ended up having to convert all the stuff to 10-bit uncompressed. I suggest using DVCPRO/HD for now until Apple gets this codec in working order.
-BTW every tech I talked to couldnt figure out my problem.
Since I rented the deck, it was impossible for me to recapture into another codec, and I was stuck.