"...really inlines get better ballistics than shotguns..."
Says who??? Are you comparing Modern Bullet ballistics to foster slug ballistics??? Apple and oranges, my friend- as different as night and day. A 12 gauge slug begins as a .72 caliber entry hole, and continues to expand and do even more damage as it goes through a deer. For the RANGE AT WHICH MOST DEER ARE SHOT, the shotgun slug in the foster style is superior to anything else smaller than it. You are listening to folks who apparently don't hunt deer where I hunt them in Illinois, and I have hunted deer in 5 different counties, both here in Central Illinois, and down in the Shawnee National Forest. ( Champaign, Vermilion, Pope, Alexander, and Monroe counties.) They think the gun has to have a scope sight on it, that it has to be able to send a projectile out to 200 yards, and still complete penetrate a deer's body.
I have friends who have killed deer out at 175 yds. with both slug guns, and MLers. ( I refuse to take such shots, but that is my business.)Both of these friends are terrific shooters, and practice so often that they never have any doubt about making such long shots. Both have ranges on their own property.
Ballistics is paper data. Its fine for what it is, but NOTHING provides the Proof in the Pudding like actual performance. Listen to this stuff, from your father, or friends, and just remember it for what it is: an opinion. Everyone has them- like noses.
I happen to have a slug barrel for my pump shotgun that will shoot foster slugs into one hole groups all day long at 50 yards. It still put them into a 4 inch groups, or smaller at 100 yds, from a smoothbore.
If I had a rifled slug barrel, I would be assured of 100 yd. groups that are half that size. But, after 100 yds, the drag factors become a serious problem for foster style slugs, they are below the sound barrier in speed, and they were never designed, nor intended to be a longer range projectile. If you can't get within 100 yds of a deer, you should be having second thoughts about firing your shot, anyway.
The light conditions in the field would have to be near perfect for me to choose to take the shot, even though I know how much sight to hold over to hit at longer ranges with my guns. There are just too many chances for the projectile to hit branches, leaves, etc. and be turned from the aimed Line of fire at those longer ranges. The chances only get worse in poor light conditions.
To Date,my shot placement on deer has been excellent, with both my slug barrel, and my MLER. I have not had a deer move more than 25 yds after being hit, and none needed a second shot. I know that if I hunt long enough, that the chance for an error to occur goes up, and my record will not stay in tact, but I am working on it every season I go out.