Good points about tape but you missed the important one: Test your backups. Having a tape is no good if you can't restore it after your system has been hacked/burnt/stolen/confiscated/mislaid. Also no good if the tapes are worn out because you cycle around the same five daily backup tapes for 5 years.
THIS TIMES INFINITY AND BEYOND!!!!
We have both a near-time replication of critical apps to DR, daily/weekly disk to disk backups, and monthly copy to tape, and limit the number of write cycles on the tape. Commvault is smart enough to flag a tape as bad if it gets too many errors on it, and it will also deprecate a tape and refuse to write to it after a certain number of cycles. (your backup application may or may not operate in a similar manner.)