I used an OS 70 on mine. No lead needed to balance, just movement of the battery. Mine was built mostly per the plan.

It's good that you used two aileron servos. I would suggest making the ailerons bigger also. I was disappointed with the roll rate of mine in stock trim.

I would recommend leaving the rudder servo in the rear, but enclosing it in the fuselage. the short linkage works excellent, but the servo is kind of vulnerable in the stock location.

The landing gear mount is probably the worst part of the kit design. If you land on the runway every time then it won't be a problem, but if you ever have a dead stick and miss the runway you will more than likely will be reinstalling your gear mount. It's a good idea to reinforce it now. I added an extra doubler in mine and use 1/4 20 inserts with nylon screws to mount my gear. This way if I have a problem it just breaks the screws and doesn't rip out the mount.

I might add that you picked the right engine for this plane too. It flies great with the 70, but the vertical performance is limited. With a Saito 91 mounted it should be quite a performer.

Have fun, I've had a lot with mine!