Is it a convenience-factor decision that drives you to an all-in-one box like that? A need for extreme versatility in a tiny package? In what context will it be used?
I think it's good for what it is -- lots of flexibility and decent tone in a small, convenient package. With that, I'd choose a hand-picked component pedalboard through a tube combo every time over a box like that, whether recording or gigging.
I never got on with the modeling pre's, but like anything it's a personal preference and we may have very different tastes. I like single coils and organic, unaffected tones, medium/low gain -- so my ear is drawn to nuances in that realm... The way a good stacked transistor pedal->high voltage tube preamp stage can saturate right at the edge of the note attack without bogging down the dynamics too much...
The modeling equivalents I've tried always sound/feel too heavy handed in that regard (to me), and it seems compounded when using them as a simple frontend before a good amp... But take it all with a grain of salt, I've only noodled around with the Vox over the course of 15 minutes or so in a music store over lunch break, through a guitar and amp which were completely foreign to me.
So: convenience and bang-for-the-buck factor -- yes, awesome. But looking at the sweet-ass stable of guitars you have, price doesn't seem to be the motivator... Is convenience?
Pat Travers used one for a long time for fly-in gigs (Tonelab SE.) If you get one cheap, catch it up. If I would look for a small lightweight amp sim, I would check out Tech 21 Fly Rig 5 myself.