I've used it on ultracoat, not monocoat. It does ok. Clean it real good then some 0000 steel wool and it sticks pretty good. The nice thing about rustoleum is it stays fairly flexible after its cured. If it sags in the sun, you can reshrink it without cracking the paint. BUT, you have to use a clean white cotton t-shirt type material laid on top of the finish, then move the iron over the cloth where the wrinkle is (dont let the cloth move around though) and the wrinkle will shrink right up. Dont paint areas that will have any friction like cowl contact points. It will rub off. The mustang below is grey ultracoat and all the rest is rustoleum. Except around the cowl contact points. Had to redo that with red ultracoat.
Edwin