Do they have a legal obligation to replace the part? It's something I specifically asked for in writing (twice) and they agreed to provide (not in writing) but failed to. They did send me a quote that listed each part they would use, but I didn't bother to look up every one and make sure it met the criteria I asked for, I didn't think I would have to. Since I agreed to the quote they sent me, does that mean they have no legal obligation to replace the part?
Also, what's the best way to get revenge on a business that screws you over? Bad reviews... where?