AJH,
I've been using my GT3 now for 5 or so years now. I've had Boogies for many more years than that so I never even bothered with the modeling (which doesn't stink, but is completely average ...which I guess means it kinda stinks
). But it does work well for stomp-box usage. I set it up for "manual" which means that simplifies the unit to 6 pedals (all user definable, of course), and it works great for what I want ...a straightforward fx unit for chorus, delay, vol boost, and the like. Oh, and the volume pedal (that's the expression pedal, that is) is excellent.
Drawbacks: cumbersome "old school" menu scrolling and buttons which is slower to use than a true fx box with knobs. Quite a few of the fx are just cheesy and useless. And a few could use a few more parameters. Oh, my fx loop hated it ...better kept in the guitar signal path.
Plusses: quiet, doesn't suck away your core tone, straight forward package that keeps all your "pedals" in one tidy package. The "basic" fx like chorus, delay, OD, etc are all standard boss quality and tone ...that's great so long as you don't hate boss units. And you can stack fx to your heart's desire.
These aren't worth much on the market so don't pay a lot, but well worth it if you get a good deal and don't want to get fancy with it. I feel no need to sell mine if that tells you anything
Edward