Gyro, in an airplane? Are you serious? They are explicitely outlawed for any and all IMAC or 3D competitions. Recreationally, you can do it but they can actually make flying the plane harder, or so I've heard... it makes the plane respond strangely. There was an article about them in some rc mag recently. (I only brought up competition so you realize that the pliots are actually flying the planes in all the 3D videos you've probably seen... there is no magic computerized whiz-bang answer to 3D).

As for big planes, the are horrible. You wind needing bigger and bigger and your wallet gets thinner and thinner. You start having transportation problems and your friends start thinking you've lost it. Seriously though, once you fly a big plane you'll never want to go smaller again. I have a 35% and I can't imagine flying a 50cc plane again... I tried to talk myself into it but couldn't.