Car and Driver said that the automatic is 0.1s faster to 60mph than the manual. However, if you want a manual, get one. In fact, order one if need be. The dealer is always going to persuade you to buy one off their lot. Plus, in a sports coupe like the 335i, there always is a demand for it.

As for the 135i versus 335i, think of it this way. It's about 90% of the space for about 90% of the price. The 135i is NOT a pure, lightweight sports car like oh say, a 2002 or a Lotus elise.

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2014 Mazda 3 GT: Ø Consumption: (click for details)