Typically I am a fan of the original Oktoberfest beers -- the few German brands that are approved to be sold at Oktoberfest, and are the real deal. I drink many other Oktoberfest/Marzen style beers, but nothing compares to those originals. With that being said, Sam's Octoberfest is probably the best American Octoberfest you can get. It's readily available, and does a great job of the Oktoberfest style. It's delicious and an excellent fall option.