USB2 enclosures really is the way to go. LaCie is the way to go only if you think five minutes with a screwdriver is worth $50.

XE says your 600£ tape drive works out to $1128 in us dollars. Newegg will then exchange those us dollars for 6.79 250GB drives and USB2.0 enclosures. 1.5TB of offline storage. Perfect for two backup of your 600GB raid array. You then setup a USB2.0 hub with three cables and three power supplys, velcro them together so they're all the right length. When it's time to backup, plug your three drives in and run a full backup.

Keep your last drive online for incremental backups, copying a new copy of every updated file to it every night. Then you've got daily roll back for quite a few days, and two compleet backups, which assuming you do them twice a month gets you quite a ways back.

Where tape really excels is when you want to be able to roll back arbitrarily. If you've got accounting data or anything else that needs to be auditable, proper yearly/monthly/weekly/daily rotations can be priceless.

all this coming from the person who "backs up" by upgrading laptops and keeping the old 2.5inch drive after I copy all my files to the new computer. Great roll back, really expensive to keep up to date though.

Matthew