I switched a few months ago to Resco Backup for the palm o/s and it is very good. I tested it out by doing a full backup and then restoring my 680 from that backup and everything went smoothly. I used to use BackupMan but it started to become really slow when backing up although the times when I restored it worked just fine.
Resco has a couple of major advantages as far as I am concerned. The most useful is the ability to do incremental backups to an existing one which saves a lot of time and makes topping up an existing backup very quick. The second big plus is the ability to verify a backup which in effect checks that the backup is okay. You can even add comments to your backups if you are that way inclined whilst deleted files can be archived. The Pro version adds back up to a FTP server but I plumped for the non-pro version which suffices for my needs.
Backing up important data on a palm device is not exactly the funnest thing you can do but it is very important and Resco Backup makes the whole process as painless as possible.