This video by Chef’s Gear UK speed tests commercial contact grills and flattop grills. Contact grills have a bottom heating element and a hinged cover with a heating element that comes down atop the items. It heats items from the top and bottom. Flattop grills have only the bottom heating element. For the two models in the test, the contact grill has one-third to one-half the surface area of the flattop grill.
The chef performs two speed tests. The first involves grilling one burger and bun, and the second requires grilling ten burgers and buns. The test showed that the contact grill cooked one burger and bun in 3 to 3.5 minutes, while the flattop grill took 6 to 6.5 minutes to complete.
When cooking ten burgers and buns, the larger cooking surface of the flattop allowed it to grill more burgers at once, so the flattop did ten burgers and buns in 10 to 11 minutes versus 17 minutes for the contact grill.
In the end, if your shop prepares many burgers daily, the flattop can better handle the higher volume. If your shop has burgers as part of a diverse menu, commercial contact grills may be better because they require less space and can prepare items for a broader menu. Choose what works best for you!