Windows backup solutions

I've been using Retrospect 5.6 for my backup needs, but it is having issues with my Promise Connectstor II NAS box (it does not work, and neither Dantz nor Promise can help, apparently). This leaves me using Retrospect only for tape backups. I downloaded the trial version of LI Utilities' WinBackup, which seems to be simple, fast, and effective.

Any suggestions out there for Windows XP backup software? I need the ability to schedule incremental backups to a network volume. That's about it. :) Oh, and it has to be relatively fast. I tried another product (NTI Backup Now Deluxe 3.0) that was 10x slower than WinBackup and Retrospect; it would have taken 55 hours to back up 100 gigabytes (I have much more data than that), which is far from acceptable.