I've been using Krylon clear flat finish in lieu of Testors Dull Coat for awhile now with no problems. Saturday I prayed a Red Caboose 10,000 gallon tank car kit with it as part of the weathering process.
The Krylon reacted with the silver paint and "crinkled" it. The black paint on the bottom of the tank and the frame along with the "Rustall" I used on parts of the frame was fine.
I can't explain it, I had not had that trouble before, Just a heads up to anyone looking to save a few bucks by using the Krylon.