Been looking into a mod called a subframe rigid collar kit. The Hyundai genesis guys are using these a lot, basically from what I can tell is this kit uses an aluminum washer that eliminates the slop from the factory oversizing the hole on the production line. which is supposed to yield better performance and better suspension geometry. I watched some you tube videos and it clearly shows a difference. Has anyone with a G done this mod and if you have can I get some feedback please? Thanks for looking