Odds are they are using deduplication to achieve this, maybe even borrowing from NBU with their Accelerator technology. So the speed improvements of 100% are not unreasonable, but at the same time, this is in certain datasets with low change rates of a certain data type.. So really, it applies to no one but their own labs.
So many people have suffered with BE 12, 12.5, 2010, R1, R2, R3, 2012, etc... That not many people left have that much faith in Symantec, let alone BackupExec anymore.
It's always been an SMB product, and has always been artificially crippled so as to not step on the toes of NetBackup. Only time will tell. Odds are, based on past performance of their products, you wont get anything stable and working till at least R2 of the release. So let's see an update to this article in 2016...