Where I am currently employed we are looking to replace our 3592 based library with a deduplication solution. Currently the higher ups are leaning towards IBM ProtecTIER without having thoroughly investigated any other solutions. Having previously used Data Domain solutions at my previous employ I was somewhat concerned that the ProtecTIER solution would be a bad fit for our environment. I have had some run ins with people who have used IBM's ProtecTIER solution and when compared to those who have used Data Domain (including myself) you immediately see the difference in how they talk about the two products. So I was hoping to find a good write-up showing in-depth details comparing the two solutions and it took a blogger like me to provide a great comparison. If you would like a good overview of how Data Domain and ProtecTIER stack up against one another in technology and performance check out the following link. It's very informative and solidifies why I would prefer using Data Domain.
One item that was not covered was the NFS capabilities of both. While I used VTL functionality with Data Domain, I was a HUGE NFS proponent. You can save a lot of money over a TSM TDP + LAN-Free solution using NFS with 10Gb Ethernet for your DB backups (since IBM's licensing costs are still questionable). When I was first exploring ProtecTIER they did not yet have NFS capabilities, so I'd like to see a NFS performance comparison between the two products.