How heavy are these ultimates you guys have?

One of my flying buddies has a 10.4 pound 64" Ultimate and has a YS 1.40 on it. I think a 1.80 would be better for him but he still does all of the 3D / high alpha stunts with it.

Lighter is better. You put too big of a motor on it and make it too heavy it won't do what you want probably.

For the 63" I would try to keep it as close to 10 pounds as possible.