I agree with Topshelf, Bridgestone Dueler H/L Alenza's are sweet.
I just put on a set of 255/55/18 on my stock rims and the ride improved 100% over my Goodyear RS-A's.
They are classified on Tire Rack as a Highway All-Season, so still pretty quiet.
The treadwear rating is also outstanding, 600!
By the way, anyone looking for a good tire size calculator, look no further than 1010tires.com.