Replacing Windows Media Server Deduplication/Tape Storage

I notice that nobody else has responded....

While build-your-own dedupe may be cheaper in comparison with NBU appliance, consider all the other components associated with server, storage, admin, manpower, maintenance, upgrades, etc. etc.

Herewith good comparison doc.

I'll throw in another option for you: dedicated deduplication storage, such as Quantum DXi and Data domain.

A few years ago, we switched from Data Domain hardware for our backup storage across multiple data centers, to using the NetBackup MSDP utilizing our own dedicated NetApp storage.  We chose our own NetApp storage versus the NBU appliances because of concerns using Symantec's relatively new hardware, based on our experiences with multiple Symantec software products.  And we were switched from Data Domain due to pricing concerns and problems we had experienced with EMC service.

You already have the right idea on pricing structure.  The other things to keep in mind are the amount of usable storage in the deduplication pool (64TB for MSDP if you use your own hardware, 144TB if you use the Symantec appliances, and petabytes of storage using Quantum or Data Domain), performance (my experience was that the Data Domain hardware was just wicked fast; MSDP using our own NetApp storage seems to be hitting some performance issues within the media servers), and maintenance/upgrades, as Marianne pointed out above. 

My recommendation: the Quantum or Data Domain option would be first, followed by the NBU appliance, followed closely by the roll-your-own MSDP storage.