Two Convertibles with some similarities, but otherwise different in most aspects such as the starting price, horsepower, market segment, ground shadow size, height, and maximum occupancy. First of all, there is a $15,540 difference in the base MSRP. The 2018 Audi TT Convertible has a higher starting price than the 2018 Mazda MX-5 Miata RF. Also, the 2018 TT Convertible has a more powerful engine than the 2018 MX-5 Miata RF. In addition, the TT Convertible is both slightly larger and taller than the MX-5 Miata RF. And then, there is a difference in the number of passengers; the Audi TT Convertible seats two more the Mazda MX-5 Miata RF. Among similarities is the body structure.