[vectorit]

I think the stick on stuff like fatmat or dynamat or the like would be best for the ceiling, just as long as it was applied well and no air bubbles allowed to exist.
The ceiling gets some condensation during the cold weather, and then the heater being on the ceiling will get wet. Just gotta be aware of that when putting stuff up there, since you wouldn't want to create a pocket or a source for moisture to collect causing rust.