Original post by: waffle911 ,
It shouldn't really matter, as SATA II drives are fully backwards compatible with SATA I interfaces, and vice-versa. If what you're looking at is a mechanical HDD, then what type of SATA interface won't matter because even a 10k rpm HDD can't saturate a SATA I connection; mechanical drives just aren't fast enough to need that much throughput. You'd only notice a difference with really ''really'' fast SSD's. That said, the MBP 17" has SATA II, as do the unibody MB and MBP 15" from before the June update. From June on, the MBP 13" and 15" use SATA I for some odd reason.