Tire Blowout problems of the 2007 Hyundai Sonata

On April 15, 2011 I took my car in to the dealership for its? annual inspection. I was told that I needed 2 new tires in order to pass the inspection and that the remaining two weren?t in great shape. I decided to go ahead and purchase 4 new tires and was immediately quoted a price. I assumed the tires would be the same as what was on the car, michelins. I didn?t ask and they didn?t say. My mistake. I rode out with 4 mastercraft avenger touring 215/60/16v tires. I didn't make a not of the dot number but the manufacture date I was 2610. On June 1, 2011 the front left tire blew out while driving on the interstate. There was a very loud pop and the tire was immediately flat. At 60 miles an hour I am grateful that I was able to safely pull over to the left shoulder. Even so, that traffic flying by while I waited for help was scary. Vdot offers roadside assistance on the highways and I am forever grateful to them for being there to change my tire. I took the tire back to the dealership and they couldn't determine what could have caused the blow out. They replaced the tire. On August 11, 2011 the front right tire blew out. By the grace of god I had taken the day off work and wasn't traveling on the interstate. I was on a city street traveling at 35 mph. Vehicle mileage was 56858 so the tires had about 4133 miles on them for the second blow out. The dealership wasn't going to help me this time and I was looking to replace all the tires. I no longer trust the tires and my life and the lives of those around me are worth far more than the price of new tires. August 13, 2011 I purchased some michelins at a wholesale club who offer warranty and maintenance. I believe there is a serious defect in the mastercraft tires that will eventually cost someone their life.