I don't have much piano/keys experience. Bought this only for the NI integration. I have used only cheap MIDI keyboards that disappointed me in any way before: Alesis VI61, Roli Lumi Keys, Akai MPK Mini and so on.
The keys are good. Especially if you have never used "weighted" keys before. Of course if you want light and synth action keys you may hate it. It was huge upgrade from semi-weighted and synth action keys for me. Like reviews of previous generations and similar products say, the keys start to make some noises and have something not feeling very well assembled. This does not affect them but you can notice it. I can see why people find this very annoying.
The build quality is good. The case feels like it's going to break but it's quite solid. I have some imperfections in some corners but I'm not sure if it was me damaging it. It's not affecting anything in anyway and it's not easily to spot it anyway.
Komplete Kontrol and Kontakt integration is great. DAW integration is much better now. The firmware issues at launch were resolved quickly by that NI forum user. Probably more firmware/features are going to be released with time but the product was exactly as it was advertised - with limited functionality outside Kontakt/KK that one day may be extended.
I honestly would put 4 stars. But with all the products that I really don't like have so many positive reviews I am giving it 5.
