I have a Magnum and a Super 10, I actually like the Super better as it isn't as heavy but they are great guns. I also have lots of 3 1/2" Bismuth and Tungsten Polymer, but I find myself shooting 2 7/8" handloads more often. Putting chole tubes in the 2nd set of barrels to make 10 gauge empties out of steel shot shells might be a plan.
We will see how close they fit with my gun when they come. Mine is a high condition field grade, but they were built to use....