I bought Data Backup 2.1 at MacWorld a year ago. I tried for months working with Prosoft support trying to get it to work reliably. Finally after they no longer answered my emails I gave up. They told me at MacWorld that they were coming out with a new version (3.0, I think) that would addess the shortcomings I noticed at the time (forget what-too long ago). Never came out. I went back to Tri-Backup.

I trialed Data Backup 2.1 based on your review but was sorely disappointed. It suddenly chewed up half of my 1.5 gigs of memory. Went from 450 megs of use to over 900 megs of use. I quickly went straight back to Retrospect which I've been happily using for 3.5 years. I would agree with you that Retrospect is a bit difficult to comprehend but it works extremely well and has saved my bacon more than once.

I found a coupon for a 50% discount for Data Backup in Joe Kissell's Take Control of Mac OS X Backups and bought it without trying (the link in the Take Control volume does not mention the possibility of a free trial). I am very disappointed and do not understand why it got 4.5 mice. I would give it no more than two! I do not use it anymore and the $30 I payed are wasted. I intended to use Data Backup for daily versioned backups of my home folder to my external hard disk, but it does not work for me. A minor problem is the lack of an option to edit saved sets. More serious is the lack of the possibility to let the program shut down my computer after a backup. What's really bad: I scheduled an interval backup every day, but instead of starting the backup after a day as soon as I boot the computer, it schedules a fixed time every day for backing up -- if the computer is off at that time there is no backup and I don't get any warning about that. What settled it was a failed attempt to restore a folder. I have compression enabled and Data Backup 'restored' the files in compressed form! The user guide does not say anything about restoring files.