FalconStor appears to have successfully added global deduplication to the most deployed VTL in the industry. Two of their large OEMs (EMC & IBM) have chosen different paths for their target deduplication products, but it appears that the primary reasons for this change were political and business considerations and not technical concerns.
The numbers FalconStor advertises are some of the best in the industry. They advertise 1500 MB/s per second of ingest/backup speed per VTL node, and 500 MB/s of post-process dedupe speed per SIR (deduplication) node. They have certified up to four SIR nodes, providing an aggregate dedupe speed of 2000 MB/s, which is roughly 2/3 of the system's ingest speed.
When similar numbers were published on Backup Central, FalconStor's competitors told us that "there's no way these numbers can be true." Therefore, we did our best to verify these numbers by seeing their VTL in operation and by interviewing customers who are using it in production. In summary, FalconStor appears to have created a product that works and offers some of the best performance numbers in the industry.