AMOFW,
If you go for a RAID 1 solution (with an alert emailed out if a disk goes down) the backup really only has to cater for fire, flood and theft.
As you say, Internet-based backup over a BB connection in the wee hours makes a lot of sense.
I'm planning an install 'n forget job
My God, man, think of all the upgrade opportunities you are eschewing!
SD