I think this one is a no brainer for any tourist.
The sandwich is so simple. Bread, mustard, then the intimate part of the sandwich, the smoked meat. Juicy, succulent, flavourful. I have to order 2 because it just tastes so damn good.
Unless, for some reason, you have a bad experience on the service side of things, you will not regret coming here. Your taste buds will be partying in your mouth for days and then they'll be sad when the party stops.