I'll have to second that. My father used the in & out spray on his '75 Corvette engine bay and it cleaned up nicely. What I found was when you first put it on it leaves the areas looking like wet fresh paint and once it dries it has more of fresh, flat & clean look to it. The hoses remained glossy and it also had a very familiar smell. A smell that other engine bays had at the local classic car shows. So, I believe it's probably widely used. This is a great product in my opinion to help maintain that brand new look under the hood.