Two Sedans with more similarities, such as the body structure, market segment, ground shadow size, height, and maximum occupancy, than differences, like the model year, starting price, horsepower, and fuel economy. First of all, the 2016 Cadillac ATS is priced $7,105 lower compared to the base MSRP of the 2013 Lexus IS 350, which is older by three model years. And finally, the 2013 IS 350 has bigger and thirstier engine; the 2016 ATS gets 2.2 more mpg. Among similarities are the body structure, market segment, ground shadow size, height, and maximum occupancy.