If you go with a .45 for bp use Winchester brass. Although I'm a fan of Starline for everything else, Winchester seems softer, thinner than Starline and seals better.
I use one and LOVE it! In my opinion it's the Ruger of shotguns, built like a tank. Yea, it's a little heavier than say an SKB, but that helps keep recoil down.
Cutting the barrels won't diminish the value, you can always get that from a SASS shooter.
If you want work done on it contact Ol #4.