its a personal question...whatever YOU like and feels good and fits YOU.

the mossberg is a good reliable gun as well as the 870. i dont have expirience with the other 2. the 500 and 870 are probably THE most popular shotguns out there...

id pick the one that felt best to me and that i liked. that being said i own a variety of shotguns. and 2 happen to be a 500 and 870. never had a problem with either.