I'm not a traditional sub person. I can't stand eating cold cuts, cheese, mayo, etc. So, typically, I'll order a different type of sub at each of the sub shops I go to.
Just to throw
@Guy 's market research off with the larger chains:
Subway: Meatball sub on Parmesan oregano bread (untoasted), with cheddar and pepperjack cheese, black olives, heavy on jalapenos and banana peppers. Seasoned with Parmesan and oregano
Jimmy John's: Regular sized tuna, with lettuce only. Hold everything else
Potbelly's: Meatball, with cheddar, peppers, parmesan cheese.
Jersey Mike's: Either a regular sized #15 (Meatball and cheese), or a regular sized Chipotle Cheese (#42 beef) or #43(chicken)
Which wich: Meatball & cheese
That being said, it's been well over three months since I've had any kind of sandwich. I've more or less cut bread, soda, and all kinds of things out of the diet