Speaking of 4*'s, I just maidened a kit built 40 size today. I'm running a .46FX in it, which provides plenty of power. It has dual aileron servos laid side by side at the wing center. It proved nose heavy, even with the engine all the way back on the mounts, and the battery as far back as possible. It's just a tad nose heavy though, and a little trim job fixed the problem. I hate adding lead to a model, but might try it on this one. It doesn't seem to want to roll very well, and I don't know what the problem is there. My 60 size rolls well.
Anyway proprunner, when you get that 4* in the air, report back and fill us in with the details. Good luck.