I have to second fhooglander's suggestion. We, too, backup a 400+GB db every night using Red Gate's SQL Backup and it only takes about 30 minutes. Restores take about that long too. Of course I'm sure we have faster disks (actually we have a SAN), but I still think you'd be pleasantly surprised by the performance. You'd save a lot of time transferring the smaller backup file across the WAN, too.
You can download a free 14-day trial copy of SQL Backup. Give it a try and see if it works for your situation. I think it will.