A couple of the shotguns in ME3 were great, namely the N7 Crusader, which fired slugs that could oneshot enemies like a sniper rifle, and the Geth Plasma Shotgun, which could be charged into a massively damaging projectile with good distance (though it actually had a tendency to miss at short range when it shouldn't).
The shotgun in Bioshock had some reasonable range as well. It was actually the perfect trade-off, gameplay-wise, between range and damage. Most shotguns are instant death at close range and water pistols at medium to long range, but Bioshock's shotgun could be used very effectively at medium range and could even pull of some deadly headshots at longer ranges if you got lucky. And the slug rounds were awesome, ragdolling foes at short range and sniping at longer distances.
The shotgun in Bioshock had some reasonable range as well. It was actually the perfect trade-off, gameplay-wise, between range and damage. Most shotguns are instant death at close range and water pistols at medium to long range, but Bioshock's shotgun could be used very effectively at medium range and could even pull of some deadly headshots at longer ranges if you got lucky. And the slug rounds were awesome, ragdolling foes at short range and sniping at longer distances.