Doomed to niche or failure
I looked at the product some years ago, it was interesting but did not really scale to what I needed. I also looked DataDomain but the cost are prohibitive, even at scale. Both rely on in-line depulication, you still have to get the data from the client.
I eventaully put in CommVault, it is stil expensive but with a properly deisgned deduplication infrastrucuture everyone else is trailing by a very wide margin. The client side deduplication is very good and exceptionally light on the network. Add synthetic full backups into that and a 20TB client will write a couple of GB of headers. Although more expensive than some, the saving from deduplication far outway the costs when it comes to investing in the disk backup targets.
I curently have over 7PB of protected data with about 650TB of data written to the disk targets. The only limiting factor at the moment is the amount of space in the remote data centre for the disk targets. I need the density to go up to 60 or 84 disks in 4 to 5 U. That problem is one that all hardware manufactures have to address, ExaGrid & EMC included.