Hi Crystal,
I have 52,700 miles on it, I switched to the Nittos last Summer at the recommendation of the Discount Tire manager. I did not want to go through another Winter with the Hankooks, this di not resolve the vibration issue. Both sets of tires are worse after the vehicle has sat for awhile. The manager said it was a Ford issue and there was nothing they could do with it. I finally got my local Ford dealer, they actually are very good, to investigate further. They rebalanced all 4 wheels and put it on the rack and accelerated up to the speed range and we could detect no vibration. The service tech told me the Nittos are just as bad as the stock Hankooks although they are much better in the snow. The Hankooks would slide even on low speed turns even though I have 4WD. Other than the very annoying vibration and shuddering mainly between 40 and 50 mph, mostly at 45, this is the best vehicle I have ever driven. The only other issue would be the rear brakes wearing out twice as fast as the front because the calipers stick.