These are both fantastic shotguns. One does not replace the other. I’m fortunate to have both. The Magpul stock is mounted with a GG&G adapter. It works nicely. I think the Aridus adapter looks cleaner, but I couldn’t find it in stock at the time.
I enjoyed Mike’s review of both M4 and 1301. With Limbsaver pads on both, recoil isn’t bad on either. I love both of mine.
Wonder why there’s so much shotgun love lately.