I've never flown any of the above mentioned planes so don't put too much into my words, but I've often asked myself the same question. From what I gather, it seems like most people prefer the Edge for best and wildest 3D flying. I've also heard many people describe the Extra as the best overall plane in the bunch when it comes to all around flying and 3D. Caps are supposed to be quite nice also. I've heard that caps are a little more tend to tip than the others, but I can confirm that since I haven't flown one. The Suk is the plane that has always got my attention for some reason. I've always thought that if I buy one of the above mentioned planes I might go the suk route. Although it seems to be the least talked about of the 4. I'd be interested in hearing about it's flight characteristics.