Codimasta, when I got mine,  I balanced it out at 73mm just like the manual said. On the maiden, I had to trim full up elevator and still add some stick just to maintain level. Let off the stick and it just wanted to nose dive! Landing the thing was a real treat!! lol  Bent the gear up a bit, but that was the only damage. Lucky! So I got on the nitroplanes support site and talked to one of their techs....he had no answer, so he ran Antonio down and told him my issue. Antonio flew the plane in the sneek-peak video on the website.  Antonio said that the CG specs in the manual were in fact wrong. I did some homework on how to calculate cg and ended up with the figures that I am flying it with now. 4 1/8" back from the leading edge of the top wing. I used the simple calculations for a non-swept, staggered wing bi-plane. Flies very nice now, and landings are really smooth.