Portillo's is better than Mr. Beef and Al's. Of the two, Mr. Beef is much better.
As far as hot dog's go, Jean & Judes on River Road and Grand is the best, no doubt. I grew up in Elmwood Park and still go 20 miles out of the way to get one.
BUT, there is some good hot dog news. For those of you who know Jean and Judes, there is a new joint in Lake Zurich of all places. It's called Delicious Redds. Amazing. It is a dead ringer for Jean&Judes. I have told it was copied from Jean&Judes exactly. The exact same menu, no ketchup for the dogs, fresh cut to order fries, and rubbery snappy hot dogs. It is in "downtown" lake zurich. If you are in the area, try it, I promise you it is fantastic.