I'm gonna use a pitts style muffler on mine. It will be better than the stock exhaust but not as good as a canister. I agree, it should have a tunnel for a canister. Maybe that'll be an improvement in the future. In fact...I'm gonna go on Great Planes website. I think they have a place for suggestions.
However, I do believe the lack of tunnel, shorter cowl and narrow fuse are a couple reasons the plane is light and has a huge wing area.
If it flys as good as I think it will....maybe the extra noise will be worth it. Maybe I'll have to go to Jtec "snubbers" to reduce the noise. That would work...
Thanks
Barry
PS: I think they said they are going to ship these the first week of October...Can't wait