Five Guy's appears the standard for this type of restaurant and price point, although BurgerFi has a larger menu and serves beer.
Comparing burgers head to head, Five Guys wins handily. Five Guys burgers are much bigger and meatier. BurgerFi burgers are small and somewhat tasty, but they're mushy and the meat is flavorless and overpowered by the rest of the sandwich.
The order of fries were big enough for two people and were decent. There are other items on the menu I might try if I go back, but for time being I'll stick with FiveGuys.
BurgerFi will probably satisfy enough people to stay profitable, but for the time being I'd say they're on probation.