It was a cosmetic change, the blades were pitched the wrong way so when the engine was running it should have been blowing like a fan lol. As far as stalling I've noticed problems in other planes. I took up a Spit-16 the other day, (rarely do but I needed quick base defense). Usually the thing is so easy to fly that I have no problems getting kills but this time it was stalling and flopping all over like a fish. Ended up landing the thing and finding something else to fly.