The taper on the wing actually has the opposite effect as mentioned above. A straight leading edge on a plane actually makes the plane more stable in a high angle of attack ( stalled harrier type maneuvers, hence requires less finesse and produces less wing rock). A swept leading edge allows for a more aggressive stall and allows faster and more precise snaps and spins, but requires more attention in high alpha flying, and landing. It depends on what you are trying to accomplish as each design has pros and cons, I prefer a Extra over a Edge because I like the snappiness of the wing design and have gotten to know the planes well after thousands of flights, but love flying a Edge around in a harrier. I don't like Yaks mainly because of the round fuselage and not so much of the way they fly, just a little draggy for my liking, the 3D Hobby Shop Slick is a great 3D bird and would probably go to it if I gave up on the Extra. They are all good flying birds and depends more on personal preference, todays designs are all good 3D machines so if you like the looks of a Yak over a Extra or a Sbach over a Edge, get the one you like, just recommend you get one from a established company like Aeroworks, PAU, Pilot, 3D Hobby Shop, etc. especially if its a giant scale, I have a couple of cheap 3D birds and like them but quality is crap but fun, the China 20cc profiles are good but built cheap and are fragile, but still love them. Good luck and remember that servos make the bird, I run cheap Solar servos on the profiles and they are great, but I stick with the big 3 on the giant scale stuff, MKS has some cool servos I haven't tried yet and Savox seems to be getting more popular.