I grew up hunting on the Air Force base where my Dad was stationed. Some of the areas on the base were shotgun only, buckshot was prohibited on base. I've killed dozens of deer with a rifled slug. They are DEADLY. You must know your limitations, however. 100yds is the practical max range (by the way, they drop a full foot at 100yds). I've killed a couple out to 125-130, but that was after a decade of experience with them. We also did some testing, by the way, and the Winchester 2 3/4 rifled slug was the most accurate out of smooth bores, and rifled barrels alike. Better than sabots, 3", fed, rem, etc, etc. Rifled slugs, by the way, are an absolute BITCH to sight in. They kick like retarded mules!
Wile E.
P.S. I shot most of my deer with a Mossberg 500 with a 30" full choked barrel, until I bought a Remington 870 and put a 20" hastings rifled barrel on it.