I just ran my new Roto 35 with a Mejlik 18-10 3 blade prop and stock muffler. I checked the sound level with our db meter and was delightfully surprised, 94dba at 9'. Our clubs current policy does not allow gas motors because of the old noise issues. I have been trying to have that rule changed to say that any plane cannot be over a set db level, gas or glow. I just proved that a gas motor can be quiet. My Saito 100 tested at 96dba.