Shotguns are the easiest to use of the special weapons, and they are also the weakest of the special weapons. Snipers are the hardest to use, but also the most powerful. Sniper can potentially 1hit kill from ANY range. Shotguns can only 1 hit kill from a very short range. The other things is consistency. Auto Rifles are very consistent (in their respective ranges). It is difficult to miss with them, and even if you miss a shot, you aren't penalized very much. Shotguns are also very consistent (in their respective ranges). You can expect to 1 hit kill in their respective ranges, and even if you miss, you aren't penalized because you can quickly follow up with a melee or another shot.