It seems good to me. The drum sounds are not the best and you can't tweak them as much as I'd like but they aren't offensively bad like most people say they are. Another criticism people have is that the percussion sounds the same as the snare which isn't true either.
The unit has a midi in and midi out and you can send note data so you can sequence an external synth. It seems better than a SQ-1 Notes can only range from C0 to Eb3 though.
Basically it's £145 for a pretty sturdy unit that's bigger and easier to turn the knobs on than the tiny volca beats (and the snare probably sounds better). It has fun flashing tricolour LEDs, velocity sensitive pads and I can use it as a sequencer.
I'd test more but the unit I received has a dodgy red LED in the 2nd position so I'm having to return it.
edit: The dodgy LED was probably because I got sent an ex-display unit, so don't take it as a bad sign of unit reliability.
this is one of the worst pieces of equipment I have ever owned in my life, my first track sampler was better than this, usually I like akai products, but this is terrible, the tweaking does almost nothing and the sounds are unexciting and dull, do better akai.