Paint...

just looking for some input on paint quality. I am getting ready to sandblast and paint my Sexton hull and am having a **** of a time trying to get some local paint shops to mix what I want. Apparently the 33070 is supposed to be the right shade, I was wondering how well the Gillespie or equivelent paint stands up to the automotive paints, as there is quite a price difference. Is there much difference between the early and late shades of olive drab? Any thoughts?
Perry