Another good reason for that high-aspect sight is the probability that the stock setup (which looks way high to me) puts your cheek right down in the hurtin' zone.
How do I know this? I've done this and now my Mossberg is back to being just a Mossberg and we are friends again. Hey, it was fun and I enjoyed playin' just as much as the next guy but now my ol' Mossy is lighter (because the SpecOps stock was just ridiculously heavy), swings faster, points better and the slide release is easily within reach of my trigger finger. 'Course she is blind at night, what with no flashlight and no nothin' else, but she can still call it out, which is likely sufficient. The unmistakable sound of a 12 guage pump slamming one into battery, don't 'ya know?
Pretty cool lookin' gun, that's for sure. Needs a few scratches though. Just kiddin'.
How's she shoot? Mine is deadly with slugs out to a hundred and fact is I lucked out and hit a packing box at three hundred a couple of years ago, which was a function of pure luck and thirty years of tournament field archery but hey, it sure felt good! I recall pointing her at a cloud...