If the gun is going to be used as a general purpose arm, I would choose a shorter barrel with threaded chokes. This is mostly a matter of personal preference though, and it is also determined by the end use of your gun. If I carry a gun all day, in heavy cover for upland game, or big game for that matter, the short barrel makes sense. However, if you use the gun mostly for water fowling, some folks seem to shoot better with a longer sighting plane. Your best option may in fact be to have two or more barrels of different lengths, which is easily accomplished with the 870, to provide the maximum versatility to the one gun shooter.