A friend had one of those sometimes back in the early oos and I coveted it, because ... well it was back then. Bringing it up to eye level, I had little difficulty getting good hits out to 15 yards or so with 00 Buck. I knew one guy who could shoot skeet pretty well with one as well.
Because it was 870 based (maybe it applies to Mossberg's too, I just don't know), it would become sort of a semi auto when shot one handed as inertia overcame the slide. It's probably lousy for the mechanism but you wouldn't want to shoot more than three rounds that way before you started thinking you had bad tennis elbow.
I might just pick one up for old time sakes.