To get a good job on an area as large as the bonnet you would want to be pretty good with a spray can.
kayl0rz, Have you tried a dent removal for the roof? the top ones now use like a hoover suction system which sucks the dents out.
kay tried that herself. she has more suction that 5 of them machines put together. I heard that she managed to suck a golfball through a hose pipe once