Well, I just tried a Quick Mission with S.E 5a. And... as much as I wanted to give it a try in a Career, now I do not. Only by the second attempt I was able to shoot down the enemy - and only because I managed to hit it's fuel tank.
From what I seen and felt, the Acemaker is not an Acemaker. Not in this game, at least. Why? Well, look at it's profile:
By this You would think it's not difficult to keep it fly straight without having to push on the joystick with all Your might - If anything, it's actually heavy up front, forcing You to pull. Well, You are wrong - ingame, S.E. 5a is incredibly Tail-heavy. Too heavy, in fact, making it painful to actually keep it do what You wants it to do. Even now, after all these trials in Quick Mission, my arm hurts from having to push as strong as I could, in order not to enter the stall, cause by it's tail. And don't even get me started how many times I almost stalled because of this tail.
Seriously, who fought this was a good idea to implement this into the game? It's a beginner's trap.