I have the Mountune radiator and have family in Charlotte, NC. In mid August while pulling the steepest hills on I-81 the engine temperature never waivers from showing 4 bars. I will also note that after installing the Mountune 3 pass radiator my fuel economy increased by 4 mpg in the city and on the highway. Turns out that the 195 degree radiator supplied with the car is the IDEAL operating temperature for this engine. BTW, winter mileage in the city is not as good, these cars drink gasoline when the engine is cold and that larger radiator slows down the engine getting up to optimum temperature. As a result winter mileage is off by about 5 mpg versus summer city driving.
Tip for the Mountune radiator and this was learned from real world experience. The Mountune radiator is thicker than the factory radiator and as a result the fan shroud is moved closer to the engine. After installing the Mountune radiator look very closely at that fan shroud and make sure that it's not rubbing on any hoses anywhere. If you allow hte shroud to rub on a coolant hose at about 30,000 miles you will have a coolant leak and you'll also find the hose you need is NOT stocked at a Ford dealership. BTW, I used a bicycle tire patch and electrical tape to effect an repair while I waited for the new hose to arrive.