Back when I was serious about control line stunt, I was flying a Fox stunt 35 with the usual 10 x 6 propeller. I decided it was not accellerating out of square corners like I wanted it to. I put on an 11 x 5, I was flying off a stooge. When I pulled the stooge line, I found myself flying about ten feet behind the airplane because of the greater accelleration from a standstill, Worked to suit me, and I have been running 11 x 5 on Fox stunt 35s ever since.