The tube does seem to be the best choice!
So far, I have always followed Randy Smith's recommendations to the letter. When he talks, I listen!
As an aside, I have always followed the engine builder's recommendations for what ever engine I am using. Most of my engines are from Randy or Tom Lay. Both have been perfect in their recommendations, and I have had the same experiences with Byron Barker.
The Aero Products and Scott Dinger tube mufflers are the very best out there, IMHO.