So get it made with a 20cm waist. That's what I did. It won't be called an MK any more because that width/topsheet/etc is all locked to the MK name. Same board though. Donek also put rounded nose and tail on mine, at my request. Sean can do anything you can think of! Why not add UPM, Allflex, Visit, Snowstick, and split board mounts to it while you're in there?
I prefer a Coiler Angry for all-day riding. There's something smoother and more relaxing about the Angry with only a tiny bit larger turning radius. But the MK is a frantic ride that's a real treat when I'm in the right mood.
BTW, you can ride an MK all day. What doesn't work is when you try to do high-energy minimum-radius turns continuously. That'll test your fitness on any board, but the performance of the MK seems to encourage it.