I'm looking to building a RAID, and ran into a thought.

what is better, fewer larger drives (1 TB x 3), or more smaller drives (500 GB x 6).

I was looking at specifically a RAID 5 or similar. Is there a difference to things like data integrity, random read/writes, etc.

EDIT: I'm sorry, I mis-spoke, I was looking at only RAID 5 (and forgot that it has a minimum of 3 drives).