Hi Chris Wilson
What is the backup cost (size) ?
Is it just ONE Server you are backing up ?
I backup around 180GB onto a rdx drive, I have selected independent recovery point set, then if you
Right click on your backup job, edit settings > Options page, then select limit the number of recovery points and select 1, use higher compression (it really compresses)
THEN :
go into "Tools > Manage Backup Destination"
Click on Settings on the above screen, and then you can select to delete automatically instead of warning you of storage.
I use the above settings, so basically when it backs up daily, after it has finished it deletes the old backup.
You can also write a batch file to format the rdx cartridge before the backup starts - so you have all space. Make sure the rdx sticks to one drive letter.
let me know if you need further assistance