Hey Paul, how many flights you got on that bird yet?

I got a tip from Ralph at RC Ignitions to use Permatex Ultra Copper. It is about 8 or so bucks a tube but will last for many engines.
Throw the exhaust gasket away, put a bead on the muffler flange and on the bolts and don't fly it for how ever many hours it says on the tube. I just took the exhaust apart on my (other brand) engine after 37 hours of flight and nothing came loose until I put the wrench on it.

Richard