Despite the clause (haven't seen it, just assuming it is so) that they can replace whatever is broken, does it specifically say they don't have to return your old one? After all, it never belonged to them. They can charge you for the new one, for installation, but what gives them the right to wipe and/or ship away your old one?
Also, you may want to contact a large tech blog such as techcrunch. If someone is in the mood they may publish your story which will put a nice amount of pressure on best buy...