If these are new tires, then the Tire maker does have a warranty of some description. They should be contacted if necessary and this is a good chance to make sure that they know fed up you are with the service that you have received from one of their dealers.
That was an interesting comment about Michelin second brand tires. They do produce some cheaper lower quality tires, some under different names. It suprises me because their real brand tires are excellent.
