I assembled one, and the only modification, other than screwing around to get the fuel tank to fit, was to sleeve the stock pushrod (flap to elevator) with a carbon tube, and to offset the rear control horn to allow the pushrod to be run through the side of the fuselage, enabling the horn to be exposed and a real Du-Bro clevis installed there...I built more elevator throw into it while doing this, so that the ratio is about 2/3.
There is a cautionary piece about the gear....I suggest reinforcing them prior to assembly (I didn't, BTW, and it has been okay).
I also added a 4 square inch "area" tab onto the outboard flap...this got rid of huge amounts of wiggle....
I think that this is a terrific flying ARF, with very little needed to get it airborne in a reliable manner.