You guys should try an 11.5x4 Apc. This prop gets the TT and OS 46 top RPM up where they seem to make more power. I was running an OS 46 with a 11.5x4 APC Ucan do. It flew really well. Another consderation is a Tower Hobbies muffler. You will see a 1000 rpm gain on the OS 46. They are 14.99 from tower. Cheapest hop up ever. After trying every APC from 10 to 12 inches the 11.5x4 is what the .46 produced the most pull with. Now if your running a OS .50 SX use the 12x4 APC. The .50 will pull that prop. If you can't find the 11.5x4 at your hobby shop the 11x4 work almost as well. The .46s are making all there power in a higher rpm range so you have to prop so it can get up there.
Jason Danhakl