I can say there is definitely not a design flaw, it was designed off of wind test models of the full scale. The rudder is just VERY effective and it is not the solution for crosswinds. The key is to keep it on the ground as long as possible and not to use rudder to correct the yaw from the weather vane effect!

The good news about the power setup is the A7 likes to go fast! Mine was flown with EDF with a TJ-100 on 10s,top speed was about 125-140 and it was very locked in at those speeds but at half throttle it liked to move around a lot. Chris Wolfe flew his with a wren 44 and it flew awesome, he now has an12s 9m setup and it moves out real nice and still lands very well at 15lbs.You definitely have to fly it like your in it and no yank and bank, fly it like your in it! Also be prepared to get on the power after you drop the gear, they have a lot of drag. The plane lands awesome but will move around a bit on final and that's normal.