This stuff is awesome! Dan still wont let me take the dropped ceiling out of the kitchen, and a magic eraser wasn't enough to clean up the metal tracks the tiles sit on. They had yellowed. This stuff made the ceiling look almost new, and SO much cleaner! It covered the water spots in the hall ceiling too. $7 a can, its not cheap, but it was worth it. It sprays straight up, it is meant for ceilings.
(my FB post last week)
A week later, I can see it is a bit splotchy around my stove, where the ceiling was a bit blackened from a cooking error awhile back.. I think a second coat might fix the splotchiness, but even if not, it looks SO much better as is!