I worked for a company that kept backups, both monthly and yearly on Tape. At the time we had several different tape types: LTO2, VXA, and DAT. Eventually the drives were sold or broken. What I have learned is that LTO is tried and true. As long as the drive is good, you have a good chance of restoring data. I got fired when after requesting for 6 months a new drive, we were not able to read data from a critical servers backup.