They were Michelin Energy MXV4 S8 I had these from the factory (35,000 miles) put a second set on wore them down (30,000 miles) and now I have Continental Extreme Contact DWS (20,000 miles now) the Continental's in my opinion are better than the Michelin's. I have a preference to change tires when they are near the end there life but if that is in the winter I will replace early.

 

Read up on the tires. The stock Goodyear Eagle RS-A's are high performance all seasons with treadwear of 260. The stock Michelin Energy MXV4 S8's are grand touring all seasons with treadwear of 440. Granted, you can't compare treadwear between brands but 260 and 400 is a significant enough difference that you'd know that the Goodyears would have much less life than the Michelins.

20K isn't out of line on 260 treadwear tires. My sports car runs on 200's and gets 12K on them. If you want long tread life then buy tires with a high treadwear rating. Buy the right tool for the job and for your needs/wants.

The inner wear is a concern but the tires aren't to blame for that.

^ This. If you didn't notice anything until the noise then you really need to start checking things more often. Tires don't instantly bald or shred (except in rare cases of manufacturing defects). There are always warning signs. Don't put your safety entirely in the hands of others by relying on the dealer.