I am currently flying with the stock OS muffler without the baffle. Removing the baffle will help improve the performance of the OS46FX.

When I first removed the baffle we had to do a minor adjustment on the carb. Since then it has ran flawlessly (the motor has run for several hours since the baffle was removed).

I borrowed a Tower Muffler this weekend and flew with it for two flights. No adjustments were needed to the carb. The increase in power was very noticable. The motor spooled up much quicker.

I'm not sure about the weight of the Tower Muffler, but my Magic is tail heavy anyway.