A bad GSIF driver can really ruin your day... Gigastudio on my machine using Staudio and MidiMan delta hardware is pretty stable (XP Pro). I\'ve only been able to consistently crash GSEdit by trying to replace samples into a live GIG. Had some random GS glitches, but only after running the app for hours at a time.
Unfortunately some hardware vendors are not known for robust driver support. Just curious, what are you using?