I bought this for practicing electric bass guitar, and it's perfect for that.
The size and layout of the device are very good: you get a lot of functionality and connectivity in something you can comfortably hold in one hand. The description "pocket" is a bit misleading, I think - maybe other people have bigger pockets than me(?) - but if it was any smaller then the controls would be too close together, and fiddly to adjust.
It seems well made, and pretty road-worthy. But I'm not planning on gigging with it - it will stay at home.
The sound is really good. Of the three MODES, I prefer O.DRIVE, which can add a nice degree of musical saturation. Of the three CAB voicings, I prefer MODERN (which adds low frequency "weight") or VINTAGE (which adds mid range "throatiness"). The "Saturate" control is mis-labeled, in my opinion; I would have called it "Compression", which it does really well; it's actually one of the most musical "one-knob compressors" I've ever used on bass. There's lots of output volume available (if anything slightly too much; I have to adjust the Vol knob quite carefully not to deafen myself).
I've given it four stars instead of five for "sound" because it's not the quietest device I've ever used. The noise level is still pretty good...but there's definitely a slight layer of background hiss, more than other bass gear I own (e.g. a mark II SansAmp). For practicing this doesn't matter; I never notice it. But it's a pity, because if it wasn't for the noise I think it would be great for recording, too. I'll try it at some point; maybe in a mix the noise won't matter(?)
As an "all-in-one bass practice tool" it's missing a few things, perhaps:
* a tuner
* a volume control for the aux input
...but I don't need them: I've got tuners already, you can get metronome apps for your phone, and pretty much anything you connect to it will have its own volume control anyway. Adding those things would have increased the price, and the size of the device.
One final thing: either I'm practising more than I used to - a good sign! - or it eats batteries like sweets. So do the planet a favour, and get a mains adapter or some rechargeable batteries :)