Question : Backup to disk Hardware suggestions

We currently have three servers that we back up to tape using Backup Exec.  The tape drive gets approximately 50% successful backups.  We want to move to a disk 2 disk backup solution.  
We presently have about 500 GB of data to backup and this number can go up to 1 TB.
So the solution needs to be scalable.  We also need to take backup off site.  We would prefer it to be a stand alone unit as opposed to adding internal hard drives to our existing servers.
Do you have any hardware suggestions?

Answer : Backup to disk Hardware suggestions

Well you have a few options -
Take the terastation off site
Fix the tape situation so tape backups offsite wont be an issue (replace drive completely/better tapes/etc)
Online replication to an offsite facility (can be very expensive and bandwidth intensive) but if you have the business need for it a good solution.