I have the Mossberg 835 Ulti-Mag. I bought it after I looked at the 870 of the same configuration.
I bought the Mossberg because it was cheaper. The action of the 870 was much smoother than the Mossber. I've found the Mossberg to be satisfactory, but mine seems to shoot very low and very right at about 40 yards no matter which turkey load I'm shooting. The factory fiber-optic sights aren't adjustable, but I found a rear fiber-optic adjustable sight at Brownell's that should work good.
I like the tang safety of the Mossberg better that the trigger guard location of the 870. I've got 2 other Mossbergs, so I guess some of my purchase was brand loyalty.
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