I have owned a passel of pumpguns over the years.
I love the 870 for accesories ( athough I don't pimp mine out!)
and reliability.
The Mode 12 Winchhesrter for sheer shootability for extended shooting becuase of its weight ( heavier)
The M37 is a lightweight, workhorse, but I do not like bottom loading guns.
The Mossberg 500 is also a good shotgun that has a very large accsesory line going for it, plus a tang safety, a plus in the feild.
I have shot the benelli, but have heard complaints from owners about its recoil.
At present, I own two M12's, and three 870's ( one is actually an express, not a wingmaster)
The '87 and '97 were fine guns, as was the '94 Marlin, but top slide guns are old technology and just not as strong.
This is not at all a biased statement, becuase my favorite guns are SXS's!
I can cycle a M12 more than fast enough to hit all the doubles on a skeet or trap field, but the 870 cycles smoother, IMHO.
I have broken two fireing pins on M12's in the past , but it is still my favorite shotgun when it comes to pumps.
Others will disagree of course, and that is their right to!
Cat