My firends shop (the one that just painted my Duster) uses a lot of water base. He hates it, especially on rainy days. My cars was done with good old solvent paint. The computer didnt have the mix for F8 green in water anyway.
I used solvent-based paint as well, mostly because I know how it acts. Also when shooting in a a garage scenario a wet floor to reduce dust is nice, but not an option with water-based paints