Well, my little Sonuus G2M came today, and I spent several hours playing with it. Let's just say I won't be returning it. At a price of only $79 I think it has more than enough application for my needs to justify the price.

Some details:
Sound source was an old technology Roland XV-3080. A lot of its patches are layered so that change in velocity actually changes the sound... but it's not as good as some of the new soft synths. But still good enough for gigs.

The G2M has two settings: chromatic (which makes the notes change in steps, as a piano would) and non-chromatic (which allows the notes to flow into one another more like a theremin)

Some patches sounded better with it set to chromatic, other patches sounded better without chromatic. Lots of patches just didn't sound good at all... particularly pianos. plucked stings (guitars, mandolins etc)

Patches that sounded usable were any that tend to be more fluid, (like a voice... remember, I'm using a MIC to trigger the MIDI)

The big surprise is that some of the sax patches actually sounded pretty good... maybe because the sax is triggered by breath and so is voice? Other good sounds were flutes, horns, some organs, most pads, many synths, some bells, and the accordion was pretty good too

The Xv-3080 has about 4,000 patches counting the expansion cards, and in 3 hours of playing I didn't come anywhere close to testing all of them. But by the end of 3 hours I was starting to get a feel for how to present sound to it in order to minimize artifacts. Yes, even with pitch correction some patches still produce glitches.

Falsetto seemed to get more consistent results than my normal speaking/singing voice.