I was looking for a small but powerful groovebox that was easy to use, and this fits the bill perfectly.
6 tracks that can each either handle audio (samples) or midi output, 64 step sequencer with unique length and scale settings per track. Knob for every function, parameter locks, per-track or ctrl-all parameters. Chance parameters. Far from being a "toy", there's a lot of powerful stuff in here - but it's all accessible. It's missing the Sample Locks of the Digitakt and Octatrack, but that can be worked around with sample chains, as the Sample Start and Length parameters can be locked per step.
It comes with 300 factory samples preloaded, and you can load sample packs or your own sounds - this needs to be done from a Mac/PC as you can't record direct. The class-compliant USB connection has stereo-out - pity it's not 6 tracks out - but you can easily mute tracks if you need to record each separately.
Super-light (800g!) and smaller than a 12" laptop - very easy to carry around (you'd probably want to put it in a sleeve, as it is plastic with knobs sticking out).
Very happy with my choice.
Edit: a recent firmware update added Sample Locks! Fantastic! Extra star for features for that.
