As I don't want to derail this thread, I try to keep it short:
For my use cases (ian's seem to be different), the amp modeling sucks. That's why I'm using external modeling. The FX are fine for me. Defenitely not much variety but very solid, kinda "instant gratification".
Editing IMO plain and simply sucks as well, regardless whether it's on-device or through the editors.
But once you accept the shortcomings (or they don't apply to your use cases) and did your programming homework, it's in fact a pretty good device. Gapless switching, usually FX trail spillover (depending on the signal path differences between patches).
Very good hardware (Boss makes things that last, the GT-1000 is no exception), super low device latency included, which allows for nesting other digital units in its loops.
More info about my findings
here.