The 6-speed isn't bad - the N55 has enough torque range that you don't really need more gears than a F1 car.
That said, if the wife wants a 28i, get one! Quickly, before she changes her mind! Take it from an old man, you don't want to override your wife's choice in cars, no matter how well intended or right you are. The happiness of letting her have what she wants is priceless. Then praise her for her choice. Her smile is worth a lot more than a silly car.