The maxima will most likely exceed in total mileage over the taurus by at least 60k, better gas mileage and be less prone to the transmission problems it seems a lot of taurus' get. However, the ford is cheaper now, and will be cheaper when it comes to things like routine maintenance.
If the $7k wasn't an issue I'd go for the maxima. Some one more qualified will probably post something better but the above is how I see it.