FireWire 800 Enclosure For SBS2003 Backups

I work for a small company that has a small server running Small Business Server 2003. We are looking into a new back-up solution. We currently have a Tarvan tape drive holding 20gig compressed and we have out grown it. Was looking into a firewire 800 card and a hotswap drive to store the SBS2003 backups and take them off site. Any feed back on this topic would be greatly appreciated.