[Montefeltro 20 jams with 7/8 ounce loads..]

Benelli recommends for all their 12 ga to use minimum 1 1/8 oz 3 dram shells. I know you have a 20 ga but it uses the same inertia system as the 12 ga. Might want to shoot a heavier load or email Benelli for some insight.

[M2 or Super Black Eagle 2?]

Orange Crush, I was in the same boat you are. I hunt mostly pheasant and quail but also hunt dove, turkey, duck and goose. I was battling going with the M2 or the SBE II. Yes, the SBE 2 is an extra $300 but it's worth it. 10 years down the road would you cough up $300 bucks to shoot 3 1/2s for that goose hunt you're going on? The SBE II is just as versatile for pheasant and smaller game but the fact is it CAN shoot 3 1/2s when you want to. Believe me, you'll be glad you did. I love my new SBE II. Let us know what you go with.