Don't post much, but where Advance Wars is concerned, Dual Strike is easily my favorite. I don't blame people for thinking the dual CO Powers thing is overpowered, because it is. But every other AW game often ends up playing out too much like a puzzle game rather than a strategy game. I don't enjoy trying a mission over and over and over to figure out the correct moves for the first five turns, which I *have* to follow if I want to even have a chance to win. And a lot of AW missions, especially ones in which you can't build additional units, end up like that, or pretty darn close.
Dual Strike, through the dual CO Powers and CO leveling system, let you play as your favorite COs regularly, and thus you can actually focus on using your preferred strategies. The almost-puzzle-game problem is practically non-existent. And it's not like the AI doesn't get to use the dual CO Powers against you.