Best sandwich: Coming up with a tie.
1.Years ago, before the quality of Schlotzky's went WAY down, I loved their original on jalapeno cheese bread. I have noticed the jalapeno cheese bread was always more moist and flavorful than their basic sourdough. And, like Subway, not all Schlotzky's are the same. The one I had in San Diego was hands down the best, the worst was in Mobile, AL. The one in Washington, DC isn't too bad, and the one in Ann Arbor, MI was so so.
2.There is a deli in Springfield, VA (about 5 miles from me) called Bozzeli Bros Deli. They serve pasta, pizza, sandwiches and subs. I have never eaten anything but the subs, and they are the best. Their most popular is my favorite, a pepperoni, steak and provolone sandwich, served hot with thinly sliced white onions, hot pepper relish, tomato and lettuce. Most get theirs with mayo, I love mine with mustard. It's messy as all getout, but god is it heaven. The secret is that like Salumi, they use only top quality meats, although they don't cure it themselves like the owner of Salumi does, they get their meats from a small distributor, not from a huge chain. Even their plain ham or turkey sandiwches are fantastic, and even better the second time around. More expensive than Subway, lol, but so much better there is no comparison.
Bad? Nothing that is burned into my memory. I love sandwiches, and like pizza, have never had one bad enough that it comes to mind.