Two flight tests totaling 3.5 hours so far on the Aero Turbine muffler (XL version with resonator built in) on the 20B powered RV-8.   Best muffler tested so far.  Quieter than even the Spintech which was the previous best.  The irritating high frequencies are virtually eliminated from the exhaust.   No noticeable increase in drag.  No increase in power or fuel economy either in spite of claims printed on the box.  The beautiful polished 304 stainless finish disappears pretty quick with the rotaries hot exhaust.  If the muffling performance holds up I'll be very satisfied.  At $79.00 it's a bargain.

Tracy