Well my buddy would rather fly inverted instead of trying to hover so he moved the CG back to 3.75" and is happy. As for the 61, well, he just loves to power things... and doesn't seem to learn. He had the SIG extra and put a Saito 2 cyl 300 in it . It weighs in at nearly 18 lbs (about 4-5 lbs over). It's great to watch him fly it and the thing really books but I don't think I've seen a plane lander faster than that one has to. He finally put it for sale in the LHS.