Which sandwich is one of Jersey Mike's most popular options?

The #99 "The Big Kahuna" Cheese Steak is indeed one of Jersey Mike's most popular options because it combines a robust flavor profile with a hearty texture, appealing to both cheese steak lovers and those seeking a filling meal. It features grilled steak, melted cheese, and a variety of fresh toppings, making it an appealing choice for customers looking for a satisfying and indulgent sandwich. This combination of ingredients satisfies cravings for both meat and cheese, while the option to customize the sandwich with additional toppings enhances its popularity.

The other sandwiches listed, while also popular, may not have the same level of signature status or the unique appeal that the Big Kahuna offers with its specific blend of ingredients, which are particularly favored for their taste and substance.