I've got a new MBP 13" (2.26, running 10.6.1) I'm going to replace the internal with a Seagate Momentus 7200RPM drive. Any reason (heat based) to go with 320 vs. the 500GB? I do video and photos (hobby, not pro), so I'd like to stay with 7200RPM. Related question: I've read here and there issues w/replacing the internal drive -- that the computer is having trouble recognizing the drive. Is this a real issue, or is it fixed.