You want very high mileage tires? How about Michelin Primacy? Sturdy, quiet--but not cheap. Nitto I believe makes a nice tire for your car but you won't get Michelin mileage out of them.
You could probably downgrade to an H tire with no safety issues but the handling might be a little less quick---usually, the higher the letter in the alphabet, the "stickier" the tire (and hence faster wearing).