On a 6TB RAID5 set, which is better 1 large VMFS, 2 medium VMFS or 3 small VMFS?

I am looking at building a RAID5 volume of three 3TB SATA disks on my Adaptec 71605Q controller. I may introduce a 1TB SSD MaxCache at a later date to improve performance though.

What is recommended in the way of logical volumes?

Should I create 1 x 6TB, 2 x 3TB or 3 x 2TB VMFSs?

The VMFSs will be used only for guest DataStores, the ESXi 5.1 OS and guest SWAP are installed on a different drive.

I'm thinking that a single VMFS will keep the drive heads closer together thus improving response time but at the cost of some queuing perhaps at the OS level whereas 3 VMFS will reduce the OS queueing but increase the head movement.

Any suggestions?

Thanks

Bob