I know one thing for fact about XXV's-they are a bit hard on a 'feller's ears.

You wouldn't think 4 or 5 inches of barrel steel out there on the ends of the tubes would matter much....but, it does. Don, I have a 20 gauge Darne with 29 1/2" tubes, and a semi-pistol grip stock, that weighs but 5 lbs, 12 ozs that it would be interesting to see strapped into your tilt-a-whirl. I plan on it being my dotterage gun, if you will.
Best,
Ted