HP Storageworks MSA 2212fc RAID group configuration best practices

[davy2k]

I would like to know if my configuration is according to best practice:

I have an HP Storageworks MSA 2212fc with 12 400GB disks.
- Vdisk1 single volume
5 drives is configured with RAID 5 and

-Vdisk 4 volumes
6 drives configured for RAID 5 as well
This volumes are created for VMware datastores.

Questions:
is this volume creation according to best practices or do we expand the volume?

Can we expand the volume by adding extra enclosures? if so what are the caveats downsides etc...

Please any manual, cbts, links to configure these will be very helpful.

Thank you in advance.