I get fifteen mini shells in my Mossy 500 using the Opsol, and the feeding is smooth. The cuff holds mini slugs. The mag tube is full of buckshot.
I guess you could get 2x the number of rounds in a side-saddle with the minishells.
I’ll need a Mossy 500 next, but supply is thin these days. Got an 870 which works well.
When I get the mossy 500, im definitely getting the opsol. Good choice, looks like you really did up your round count.