F4U-1A. Doesn't climb real well but it's fast, dives well, stall fights well, and has a decent ammo load.
I flew the F6 quite a bit yesterday. That's probably my second favorite.
For bombers I like the 17s, very rugged. I also like the 26s. They are so fast that it's hard to get a good angle on them except in a very fast plane.