So I bought a set of 9" carbon fiber props and tried them one time, and instead of hovering after take off it kept going up, and to the right. It was necessary to correct this by decreasing throttle and moving left, to keep it in a hover. The moment I center the controls, up and right it goes. - Is this a balancing issue? Or is it because these props are creating more lift than the stock ones? - also, sellers say that these propellers will also help get more flight time out of your battery. I really didn't have time to test that myself, because of the drift I mention above. But are these propellers in fact more efficient, thereby extending flight time on the battery charge? Thanks.