Disk drive access speed isn't a factor, since the player uses an aggressive caching algorithm that leaves the disks spun down most of the time. Any modern laptop hard disk should be fast enough, and you will not notice any speed increase by purchasing a faster disk drive. In fact, if choosing between a fast drive and a slower drive, the slower drive is probably the better choice because it will most likely be cheaper and produce less heat. Your biggest concern will be the price/capacity trade-off.