I vote AK47 in 7.62x39.
I own three, and love them.
My vote is biased though as I don't yet own an AK-74 (I am eyeballing kits to rebuild though....).
I figured (for now) if I want a smaller round with flatter fight path I'll shoot my ARs.
21 Club #150 California Glockers #150 Kalashnikov Klub #150 Black Rifle Club #377