When car with paints containing iso which mask is the safest. Full face mask with supplied air. Or hood mask with supplied air

If used properly, either one will provide excellent protection as they are both supplied air meaning that they provide OSHA Grade D breathable air to the wearer.
The question is - do you wear prescription glasses? If so, a full mask might be better as the hoods have a faceseal that makes wearing glasses slightly more difficult.
How much overspray do you have? Do you ever paint overhead (i.e. trucks, etc.)? The hood is more protective from overspray.
I also like that the hood can be flipped up without having to be removed when exiting the booth.
In the end, it will come down to personal preference. Try both and see which you like best.