I replaced hard disk drive of my MacBook Pro which I use for Traktor with 500GB HGST drive.

Every time I tear down this MBP (not unibody), lots of screws annoy me so much. I refered to iFixit, and replaced the internal hard drive with new one. It has enough space to store original audio data for mixing songs (I guess about 10,000 songs in wave format). I know there was a choice for more storage. 500GB is reasonable price at this time. And I like HGST (HITACHI brand), it's quiet and much reliable.