...of course it depends on the data that you want to back up, too....
If you are worried about e-mails, etc...than definitely pursue the Outlook PST options some more (I personally have two or three PST's at work)
If all you are worried about is the info you would find in your "native four" Palm apps - then a simpler and faster way may be the "backup to Palm Desktop" option that Chapura's Pocket Mirror offers. You can do this when you synch ( I do it every so often for the "just in case" factor).