Having run RAID quite a bit myself one must remember having all your drives in one box is always an invitation for trouble since hardware failures on a higher order will likely hit all the drives.
If you want to do online backup get DSL instead of cable internet for the faster upload bandwidth.
Get a backup service with versioning. That way if you or a virus delete something it just doesn't sync the deletion to your backup.
I personally use JungleDisk which uses Amazon S3 storage. You can set the versioning controls and you only pay for the storage/bandwidth you use. My bill averages about $2/mo for several gigs.
Yes I heard it has gotten better over years but I still see computer after computer crippled by their bloated software. It wouldn't surprise me if it was a rootkit of some sort which was used in older versions of Systemworks.
I got rid of Norton after I saw such a huge hit I was taking on startup time and hard drive access time. If you check comparatives on anti-virus products you'll find many offer the same or better protection without the performance hit.
Personally I have been very happy with Nod32 by ESET. Its startup is slower on my personal vs. work machine and I had to have it exclude some areas for false positives but overall it has been very efficient.
Our business in life is not to succeed but to continue to fail in high spirits. -- Robert Louis Stevenson