Originally Posted by
Chefboiali
London Broil is good to marinate. Other than that, rare to medium rare on the filet mignon.
Coals forever > gas.

"London Broil" is the biggest sales gimmick of all time. Do a quick google on it.
London Broil simply means thicker than a steak, thinner than a roast. Generally they are cut from Sirloin Tip (Knuckle between whole Round), or Top Round.