You will find the E much more enjoyable in the MAs. The B is quite the challenge. For one, you're slower, climb worse, yet still have to get in closer to do damage with the .30cals. Getting in closer is hard when everything runs away.
Then there's the problem where they don't want to let you leave. I had numerous folks chase me down over TT/FT in a P-40B. Had to get some local cover to help me egress when I was rtb, otherwise I'd never have made it.
B is much more of a "I'm doing this as a personal challenge" type of ride. The E is rather pleasant, as Klam mentioned. With the .50cals, however, you can still reach out to 350 yards to pop somebody. Just note your ammo clip. Only slightly less than a P-51D. It's the same 267 rpg you find in historic P-47 loadouts as well.