For a single osc synth, I must say its pretty fat. I can't really compare it too much because I haven't tried many analogs. I won't say its as deep as a Little Phatty, but it has a creamy analog buzz to it. I admire its simplicity and limited capabilities, I'll probably pick a few of the presets I like and stick with those. With other synths that have alot more presets or sound capabilities, I tend to toy around too much and fail to make anything good. I like the knobs, I can make subtle changes to the sound on the fly rather than obtuse botches.
There are six presets with five octaves each. The synth has AR EG (the release is labelled Sustain), modulation with repeat and random repeat, and vibrato, which can be routed to the oscillators or the Traveler. Modulation has depth and rate control. There is a switch for portamento and pot for the rate. And there's the Traveler, which is Korg's early equivalent of a low pass filter (and allegedly resonance, though it doesn't really sound like it has that ping to it). There's also a knob for pitch, which I'm sure is there for tuning, but I might use it as a subtle pitchbend-esque effect.
The Micro Preset has a really particular set of sounds. Unlike the other presets, Synthe 1 doesn't sustain and has a really fast envelope, so to sustain the sound, I use the repeat function with the modulation rate set all the way up to 10. It seems the level drops with repeat on Synthe 2. Synthe 2 has white noise and pink noise in place of the 4' and 16' octave settings. Brass isn't effected by the EG and it has a pretty steep decay, but unlike Synthe 1, it sustains. Strings, Wood and Voice aren't effected by the Traveler or by the EG.
You can mix two presets together, which seems to work well in almost any combination. The level drops out a bit when you mix Synthe 1 & 2. But other than that its pretty effective. I might use it alot with the String, Wood and Voice presets to add a little functionality to them.
I'd say this thing is great for bassy, buzzy and vox tones, and for an all around archetype synth sound. The noise presets are pretty sweet, great for swishy, stormy sounds. They suprisingly mix in very well with another preset, shame they're stuck with 4' and 16' settings. The overdrive on my amp really brings out the beef in the bacon. And I bet this thing would sound even more haunting through some reverb, chorus, flanger, or other effects of the like. This thing sounds great, its real creamy, and its minimal interface is great for just jumping right into some music.
Sorry for the long, over enthusiastic review. Videos and better pics to come.