The only reason I give 4 instead of 5 is that I had hoped to use it for microtonal music by reprogramming it with midi messages. It does accept pitchbend messages (despite not having a controller for that) so it is possible to use monophonically for microtonal music. It does listen to all midi channels (omni), so I thought it would be possible to reprogram it for 16 notes microtonal polyphony, but no. The channels are merged and then separated into different voices. As far as I can tell, not merging the channels would be a trivial feature to implement in the firmware, that's why only 4 for features. With that out of the way, it's a device that feels great, looks great and sounds gorgeous! My hands are not particularly big and I actually like these mini keys better than normal-sized synth action keys. The knobs are a bit more plasticky than they look in pictures, but it still looks great and plastic makes it lighter and more portable which is arguably the deal with this instrument. The instrument sounds are amazing and the effects are really well tuned to each instrument. The only exception might be the toy piano which is a sound I don't really love (even though I do like the Amélie soundtrack). With sustain, tremolo and reverb, it can be made to sound more like a vibraphone though. Some have commented on the hidden piano sound, but I personally find nothing wrong with it and consider it very useable. The speakers sound good for their size but of course they are very small so don't expect to get a lot of bass out of them. Also you need to hit the keys with a bit of velocity as they are a bit quiet for the lower velocities. Loud enough for playning in the garden :)