Illinois has a split gun season. During our first Illinois season, I always rifle hunt in Northern Wisconsin with a rifle. I hunt Illinois the second gun season which is 4 days - yesterday thru Sunday. This year I used my 20 gauge NEF Ultra Slug Hunter with Lightfield Hybreds. I shot an 8 point yesterday and a doe this morning. I have always preferred a rifle, but I almost always shoot somewhat downward from a tree stand and KNOW where my bullet will go with a pass-through or a miss. I will not shoot an animal on a ridge line, although I have been urged to by excited hunting partners. I do think that there is a place for slugs vs. rifle cartridges, considering the behavior of some people who are not as careful as they should be. I also think that most places in Illinois could be safely hunted with a rifle if all of the hunters were as safe as they should be.
This year I chose the 20 gauge USH in place of my Savage muzzleloader for the Illinois hunt. When I zeroed my guns in last week, I was again astounded at the accuracy of these inexpensive slug guns with the proper saboted slugs. Many shots touching at 100, and all well in the center of a 2" bullseye, not even close to the edge. 385 grains at 1500 fps is pretty authoritative when you can put it right where it belongs too. The buck yesterday got lunged through the ribs at 70 yards while walking downhill into a draw. He stumbled about three steps forward and crumpled.
It was 3 below this morning where I was hunting, and for the first time ever, my USH firing pin didn't hit the primer hard enough when I pulled the trigger on the doe. Dented, but no discharge. I changed to another shell (Very accommodating doe, waited) and tried again with the same results. The doe took off across a pathway, got about 80 yards in some thicker stuff and stopped facing away from me. I put it on the base of her neck and hit the primer again on the same shell. This time it went off and she disappeared below my line of sight. When I climbed out of the tree and walked over to where I saw her last, she was on the ground with hole at the base of the neck, exited the high chest/throat area and reflexively kicking a bit. I couldn't have placed the shot better with my .308, nor would the results have been any better.
I need to take the stock & barrel off of the USH, flush out the receiver and get rid of any oils that would gum up at cold temperatures. I have done that with other H&R/NEF guns, and I assume I "missed" doing it to this one. That almost cost me a deer.
On the other hand I have a "refreshed" respect for 20 gauge slug guns with good slugs. The little USH is pretty trim and handy in 20 gauge. It is a very safe action - that's why I always started youngsters out with these. The Lightfield Hybreds are expensive as are all sabot slugs, but after you zero your gun in, you don't shoot many anyway. The 20's are absolutely stone deer killers though. They have the physics and the accuracy to get the job done - easily to 125 yards, and more if you know your business and have the shot.
I love my rifles and muzzleloaders, but honestly that cheap little 20 with those expensive sabot slugs can get the job done, and I won't feel at any disadvantage whatsoever where I hunt in Illinois or any other slug area. I have a Nikon Buckmasters scope on it, probably cost more than I paid for the gun, but a decent scope can't be beat.
I had one of the 12 gauge USH's once, but that one is just too heavy for my tastes.
Some posters have mentioned handgun cartridges in rifles as preferred. One of my first deer rifles was a Ruger carbine .44 mag. If I recall, I was getting about 1700 fps with 240 gr. factory ammo. I killed a few deer with it. It was not as accurate as the USH and not as "powerful". I know there are several more pwerful handgun rounds now, but I have no experience with them.