Question : Determining Size of Disks for Exchange 2010 Migration

Plan on replacing Exchange 2003 server with Exchange 2010 server.  The calculators online are confusing, and don't necessarily help with the understanding of the growth of data that we have on our 2003 exchange server, and how it will grow on the 2010 server.  Need some recommendations on how to proceed with the ideas I have, if the configuration is sufficient or if it's overkill)

Current sizes on Exchange 2003 server with 483 mailboxes :
Raid 5 across 3- 136GB 15k RPM disks split into 2 partitions (12GB OS & 260GB application)
mdbdata: 95.5GB (edb size:75GB, stm size: 24GB, E00XXXX.log files ~1GB)
mail.log: ~200MB

Proposed setup on new Exchange 2010 server running 2008R2 server
Raid 1 across 6 disks, split into 3 groups
(OS- 146GB RAID 1) (Logs-146GB RAID1) (Database-600GB RAID1)

The size will also most likely be reduced eventually once we implement a vaulting/deduplication solution, which will decrease the size of the mailbox store.

Answer : Determining Size of Disks for Exchange 2010 Migration

Excellent.  Good work