Michael,
First it is a pistol, not a rifle. Pistols are typically used at short distances. The GK1 is NOT a plinker. It is powerful enough to damage unintended infrastructure. I own a V1 and a V3 in .25 and have hit pigeons at 100 meters. It is also a revolver and its munition retention in the magazine is a chamfer machined into the magazine's bores that catch the skirts of pellets. Slugs do not have a skirt and the only way they can be retained is friction. In other words, the gun is not designed to use slugs, nor do slugs at the intended short distances, add any value., only more cost If your intended use is for high power and exceptional accuracy is your requirement, then the .25 is superior to the .22 . The GK1 is also loud. It needs a good moderator. The higher the power selected, the louder it is. Only you know your intended purpose. Your call.
