I forget if I answered your main question. With Backup Assist, you can overwrite or append or do differential/incremental backups. Or, if you choose, you can set it to do 10, 100, or 1,000 backups before deleting the first one. Or you can set it to use up all space before deleting the oldest backup. Or you can set it to leave 10GBs of space before deleting the oldest backup. It will do whatever you want it to do.
I will say this again as I alluded to it in my above post and forgot to address it. I have said it in many of my backup posts. The chance of your needing your backup due to a hard drive crash is probably 1 in 100. The chance of your needed a backup because you lose a file is probably 1 in 10. Don't know how many times, my nurse has deleted a fax that came in. All I had to do was go into VSS or a backup and get it. The more backups you have the better your opportunity to go back and grab a file that you discovered missing four weeks later. You can't do that if you sync. You just synced your data with the missing file. So you have a perfectly synced hard drive -- just don't have that file you are missing.
