the MVVS 26/ Evolution 26 is really at the top of the heap-
with the pipe (which by the way is easy to install) -required no adjustments and puts out great reliable power.
Many users have the factory pipe -no one else in that class size has anything to compare powerwise
the ear splitting "mufflers" furnished with some engines are not mufflers .
In my book the review by QQ on the YAK did real dis service to the 26- The engine on the Evolution muffler does do decent 3d and at a decent noise level- on 9.5 lb models .
at 10 lbs the piped engine is still a rocket setup -up here -- at 4350 ft elevation.
Poo poo it all you like but unless you have tried one or flown one on the pipe especially-you can't appreciate what the very compact, little powerhouse can do.
the claims are not wild -