If your lifestyle is limited to bedroom role-play, go for it. But I would not think it would work for a 24/7 relationship.

HOWEVER: Subs often have trouble expressing what they want in a scene. If you do a switch - chances are the sub will behave the way they WANT the dom to behave so it might be a good learning experience.

Ideally - if your sub wants to play dom, find another sub for them to work with and watch what your sub does.