I could see this being a valid point with someone that takes a few cans of the stuff in an attempt to paint a vehicle.
However, with the correct prep and process (using a HVLP sprayer and 5-6 coats) I don't see the difference between this stuff and an expensive vinyl wrap? I've seen video of professional jobs being sprayed point blank with a pressure washer and seen road grime washed off with soap and water.
I'd love to hear more about your experiences with whole car dips though as I'm honestly trying to make an educated decision. So far, $300 for plasti dip is looking a lot better than a $3k vinyl wrap.
