I'm not looking to start a war here, but I don't agree much with the last post.
Pumps are more reliable, and you can forget to pump, but autos can and will fail to cycle if not firmly mounted, same as a pistol will. It doesnt happen often with a quality auto, but it does happen often enough for that to be a consideration. IMO, it washes out the "speed" factor.
A 20 or 410 is lighter, built on a lighter gun. But, the power factors are the same. The only difference is the size of load delivered. So, you may be shooting a lighter load, but the size of the gun washes out any recoil advantage of having the lighter load. The only penetration difference with the different guages matters when talking slugs. #4, 7, 6's or 00 are the same no matter the guage. The difference is in the numbers hurled down the tube. If you are worried about penetration issues, slugs are out of the question anyway. With proper training and knowledge, the smallest of people can shoot a 12ga with no problems. I have a 10 year old do so now, it just isnt as hard as people make it out to be. So why limit yourself with poor SD ammo selection?
Also, comparing a Judge to a combat shotgun is apples and oranges.
To answer the question asked, the 590 is a solid choice.
Sorry about the rant... Good Day!:bier: