There's absolutely nothing wrong with Redline's product quality, if the complaint is whine at low speeds/turning (although it doesn't bother me at all, it really isn't that bad in my car.) But to say Redline caused SRT-4's or any other car's syncro's to go bad is ridiculous. That's just spreading a bad rumor about a good product. Like I've said I used the Ford XT-M5-QS too and it is a great product as well, so if the whine is too much for you guys that are complaining then go that way, I will say it again both of these products do a very good job....