Regarding balancing...I've used the GP CG rig to balance my planes, inluding a .40 seagull zero which, even with a TT .61, took 9oz of lead on the nose to balance to the book spec. It flew great and landed like a trainer, and was around 95mph until I tried some not so warbird like moves with it and ended up inverted about 10ft off the ground after a square loop and apparently I grabbed too much elevator and the engine sputtered on acceleration and it went in. It's a pile of sticks now. I've been looking around for a replacement since the seagull is hard to find, and I've been leaning towards the CMP model. I'd like the 120 size as it seems to have less problems, and my buddy has CMP/GSP corsair that size which would make for some neat dogfights, but pricing may send me towards the 50 size since I already have all the gear for it. Back to the balancing part... I've read in a few posts of people who use a plumb bob to find the cg of any plane. Apparently you suspend the plane from the wings and the tail, and let the plumb bob hang at the point that the whole plane is hanging from, and where the bob points is where the cg should be. Can anyone clarify this method and if it's reliable? Thx.