We used to run the Fox .35 in the Foxberg races. They would shake the fuselage to pieces without a cheek cowl. We have since gone to LA .25 motors, and they run very smooth and just as fast or better than the old Fox .35. I think maybe the Fox could restart a bit better if they were not run too lean though. I was kind of mad when we were forced to go to the LA .25 because I had to buy another motor, but they are pretty good. I am still stuck with the old Foxes that will not accept a muffler. The stunt guys around here are using the LA .40 and .46s now to still give the 4-2-4 cycle run and still run slow enough to give the 5 second laps. Because this is the Fox club, I will affirm my love for my Fox .15 BB. Runs fairly fast for an iron piston, and idles down to nothing consistently. Kind of a shame Fox manufacturing is winding down. Old Duke was full of quirky and great ideas, and acted on them. Always a leader not a follower like the others. Not a whole lot of development went into new designs since his demise. Just tweaking IMHO.