I have the black nitrided version of the MkIV. Sold off a MkIII standard to buy it to get the threaded barrel and the push button take down. Glad I only had one MkIII as i would be tempted to change out all of them for the easy takedown. As mentioned the factory sights are not good. I bought a replacement leaf for the rear sight that turns it into a peep sight and combined it with a Dawson Precision fiber optic front sight. Groups tightened up right away, unfortunately they were low (too tall of front sight), new front sight is on order. It rides in a BattleCloth holster / carry case that holds it with the Dead Air Mask mounted. Nice combo that has eliminated a few squirrels from the birdfeeder.