It is when you know how to shop. I'm not saying it isn't gonna be $7.00 but it removes the hassle of mixing. The resto shop I'm associated with can get bulk orders and pass a savings to me. If you got to the store, try a military discount, look for sales, any way to save money it obviously positive, but in the end if the Rust-oleum is cheaper, roll with it. As long as the car is painted, job done.