Longhorn,
I used the Eastwood Extreme chassis black on my frame.
My only complaint with it was that after a good cure of 2 months a leaky M.C. dripped overnight onto the frame and a-arm on the drivers side, it stripped the Eastwood down to the bare metal in NO TIME!
I used POR15 on the underside of my hood and a few other places it seems to be a LOT harder than the Eastwood product.
If I had to do over I would go with the POR15 for my frame and other OUT OF THE SUN places.
Just my review of the product.
Tim