The 2012 Mercedes-Benz SL-Class is available as a 2-door, 2-seat convertible. Starting at $103,650, the 2012 Mercedes-Benz SL-Class SL 550 is powered by a 5.5L, 8-cylinder engine mated to an automatic transmission that returns an EPA estimated 14-mpg in the city and 22-mpg on the highway. The top of the line 2012 Mercedes-Benz SL-Class SL 63 AMG, priced at $140,440, is powered by a 6.2L, 8-cylinder engine mated to an automatic transmission that returns an EPA estimated 12-mpg in the city and 19-mpg on the highway.