I was brought up hunting deer with slug guns. A few years ago however, the state legislature started thinking with their heads (at least on this issue) and adopted rifles for my home county.
During my young years, I used alkl types of shotguns, starting with plain smoothbores and bead sights. Although Foster slugs were not "reccomended" for full choke barrels, many guys shot such slugs through them. Accuracy was spotty.. some guns fairly good some guns abysmal. Choke pattern didn't seem to make much difference, because with bead sights the pattern was rather large.
When smoothbores with rifle sights came out, I had Ithacas in both single shot and pump guns..plus used others. The most accurate smoothbore I ever shot was an H & R single..got several deer with that. Shotgun slugs from 12 to 20 guage are very hard htiting and do not lack in the least for killing power.
When the gun companies decided to build smoothbores with rifle sights and try for the most accurate shotgun, they all used "imporved cylinder" or "cylinder bore"...there must have been a reason.
Some folks thought sure 20 guage slugs "carried further" than 12 guage..but tests have shown that to be a false assumption. On the other hand the 20 has a milder kick and is still fully adequate for deer....and more..
Today's rifled shotguns can rival centerfire rifles for the first 150 yards or so... but those sabots are very costly....