Hmmm - That is what I was thinking about the cans - I've done a couple of rattle can jeeps & I've even painted one for real with a base / clear - it turned out really nice.
I'm hoping not to get too involved in this for just a bumper and grill, but then again - I don't want it to look like crap in 6 months either.
If I could find a good hard finish in a can I'd jump on it. If not - I'll bite the bullet & buy the good stuff.