Over the years I have shot a lot of shotguns (not as many as I want to shoot though) including both of the ones that you are listing as well as the Mossberg 500.
With shotguns, the "feel" is extremely important even though you will be using rifle sights or a scope for deer hunting, so going to a sporting goods store or gun shop to feel them or even better a shooting club were you can "rent" the different types and shoot them would be even better.
I have four shotguns in my gun cabinet...three of them are Remingtons (M870 in 20 gauge, M870Express in 12 gauge, M1100 in 12 gauge with 28"RC barrel and 20" fully rifled barrel with rifle sights).
I found the Mossbergs to be heavier and not as smooth as the Remingtons...I also disliked the tang safety on the Mossberg compared to the crossbolt safety on the Remingtons.