I purchased a pair of Nike Mercurial Vapor IX shoe...

I purchased a pair of Nike Mercurial Vapor IX shoes (which retail for $225) from SoccerPro that tore after the second use. After a number of back-and-forth emails, I got SoccerPro's representative to agree that such a tear is not normal (although their official policy is that a tear is a defect if it affects the performance of the shoe). But even after agreeing that this shoe is defective, they won't offer me a refund, only store credit. That might have been sufficient, except they no longer have the shoe I purchased in stock, so I'm either left with (1) a shoe that tore after the second use or (2) a store credit I will not use. Needless to say, I will not be shopping with them again.