I beginning to think this stuff is like gasoline, and I haven't had a bad one yet. I ran out of some SPI clear for my brother's truck about 6 years ago and used Nason on the hood, the entire truck still looks great, including the Nason. A friend used some $60 for a gallon set up 4:1 on his van about 5-6 years ago and it's never washed and still looks like it was sprayed yesterday, he sprayed 3 coats, never garaged.