I go to the chiropractor frequently for my back. Ceilings are killer on the shoulders. Perhaps you should avoid them. We have a guy here named Stansoph who only does trim. I bet he could give you some marketing ideas on avoiding ceilings.
And in ordinary (non-deep base) colors, it doesnt cover any better than regal. This is the real mystery of Aura...Aura on ceilings wow, thats expensive paint for ceilings.