I will say this; when I want to be a "Tweak Monster" (as opposed to a cookie monster), I make new sounds on the Kronos...now THAT is a lot of fun. I've built at least 25 Combi's on the Kronos to cover songs for our Wedding Band. You just get lost in that keyboard and it's just great fun. Tyros 4 is really a different animal; more like a bread and butter keyboard. It does what it does and it does it well. The Kronos, on the other hand, is limitless.