Performance. Symantec product management and SE's will claim thae dedupe makes backups faster. It does not. It's about the same. You can throw dual six-core 16GB RAM servers at it, and a single quadcore is just as fast as processing the deduped data. The dedupe engine is not multi-threaded to take advantage of multiple CPU's or cores.
Varying dedupe rates. Symantec doesn't have a good grasp on all data types and how to dedupe them. Vmware was problematic until R3, where you would get 20:1 in one pass, kick off the job immedately after and get only 8:1 when the OS was idle doing nothing! Exchange, and SQL are the same way too. I'm not sure how your linux, Oracle or Netware will play out. I have no faith in it as an all enompassing solution, only that it's good enough for the price.
The Vmware agent has been solid and works well. In fact better than NetBackup IMO. Easier, cheaper, and just as fast! I've had little problem with it using SAN based backups to disk or tape. GRT of files works great too. Though GRT of applications has been touch and go, so I stopped doing that, and use agent based backups for that.
Oracle RMAN integration... Becareful if you need support. I hear there are only 1-2 people total in that team. Based in Florida IIRC
At the end of the day, the price is hard to beat. If your data set is under 5TB, I think BE is fine. Go over that, I think you have had outgrown BE. Or if Dedupe is important to you, get a more stable and proven product like an appliance.
