Have you tried the latest EMC Avamar ?

Avamar supports Extended Retention Media Access nodes -- A Media Access node exports backup data from an Avamar server to a tape library (physical or virtual) for long-term retention purposes. It has an HBA port that allows a tape device to be connected directly to the node…

Meets and supports the max and min configurations mentioned in the guides Admin and other related docs are precise RTO and RPO's are defined properly Is a popular solution around Has a strong Tech support Many Blogs and whitepapers written around their solutions Cost…