Alignment for RAID5, ESXi RDM, EXT4

[Callek]

I have some new drives on the way home. I have orderd 5x WD RED 3TB no need for 7200rpm drives that's the main reason I went for the RED's.

System
HP Microserver
HP P410 256MB BBWC
RAID 5
ESXi 5 (plan is to run RDM)
Ubuntu Server 12.04 LTS (EXT4)

How should I align the disks? Initial plan is to run 64kb stripe size and align the RDM volume with gparted manually. Is there something else I should think about (besides that RAID6 is better considering the volume)?

 

[kac77]

Since you have the battery backed cache. I would go RAID 6 for 3TB drives.