i did mine with the stuff wis recommended andits still going the same as the day i applied it.nevergot a spec on the filter and had the cover off several times no sign of peeling.dampens the sound alot.going on 1 yr
I don't have much time on mine but it sticks to the cover like gorilla snot does. (If you don't know what gorilla snot is, look in the auto parts for a tube of 3M weatherstrip adhesive, it's nasty stuff).
I think the issue of ths stuff ever "peeling off" was because the dry time for a thick aplication was not met. It will form a skin in a half hour but the stuff under the surface will be mushy for a long time. Anything over a 1/4 inch will take at the very least one day before the next coat. I guarantee if it is applied properly it will never come off without some major swearing and cutting.