I have both the CK61 and the Vox, actually three of the latter, a 61 and two 73s on top of each other on that great stand.
Love the Vox, as you can imagine. It’s an instrument indeed, that’s the best way to describe it.
Love the CK61 too, for all it can do, but especially for noodling on the couch.
It’s like an MacBook Air.
And I’m getting a Grandstage X, which has the Vox sounds in a 88-keys weighted keyboard, with almost double the sonic content of the original Grandstage.