Tell you what one of the best I ever had is my ss cobalt, just keeps on ticking. 32MPG to boot around here. Horrible on tires though the way I drive it.
A tangent on the question is what's the worst car you had that you loved?
I had an early Isuzu Rodeo with the Chevy V6 in it. I think the heads were warped by design. That thing was like the Batmobile with a massive cloud of smoke every time you started it.... then going up hills it would lose speed like an overloaded semi... but it looked cool ...