This piece of kit is incredible. IT's not for the faint hearted though. If you don't know sound design I'd give this product a miss for now. You really need to know your stuff with this machine. But that said, it doesn't take much to tweak the presets and get your own sounds.
The synth is very small and like most of the boutique models you will struggle to use if you have biggish hands.
The sound is insanely good. It's loud and packs a punch. You can make anything from your sub bass lines through to your melodic long release pads and synth lines. The built in sequencer is ok. I find the plastic buttons a little annoying at times, they feel a bit cheap and flimsy for me. but I'm used to having equipment with keys or ouch sensitive pads.
If you take the time to learn this machine and get over the initial shock of how teeny it is, you'll definitely be using this in your main set up! Also added bonus - unlike the boutique stuff, this doesn't run off mini usb 5v. It comes with its own 9v adapter! I'd highly recommend getting the k25m also