I did have an O.S. 46 fx on it at first and it would torque roll. I was just bored with it. It will do knofe edge loops. The flatest spins I have ever done. I have also landed it twice doing a flat spin that is how flat it gets. I will post more pictures of the mods on my site. Go with the .61 and get the cg to 4 to 4 1/2 and you will love it.