Don't knock the 5-row chromatic keyboard until you have tried it. If you had NEVER SEEN a standard "piano type" keyboard, then maybe you would have welcomed a system which has no "2nd class" keys (the black ones are shorter, narrower, and generally a pain in the neck). A chromatic buttonboard, however is so instinctive that it is soon understood - only one scale to learn, only one set of chords, the ability to easily span up to two octaves with the right hand. If you watch some of the French, Scandinavian, or Russian players, you will realise that some of their music would be impossible on a "piano" keyboard. The version of the KN7K has a full 120 bass (as in a regular accordion) and the treble buttons have a bigger range than most other keyboards.
Mike O'R