"...A warranty has absolutely nothing to do with how a product will perform. That is like saying that you will live longer if someone sells you life insurance. Remember when Chrysler went to 7 year powertrain warranties? Do you think they redesigned the engines that year?"So why did the Japanese cars have better warranties than American cars? their quality was much better than the Americans'."...The issue with hitches on E53's (that is the only model that I researched extensively) is not the hitch itself, it is the design, and by extension, the attachment method. Those 6 holes you reference are all drilled in the bodywork. There is no frame on an X5, it is a unibody design. In my opinion, it doesn't matter if you use a few or all of the holes in the bodywork, you are still attaching a trailer hitch to sheet metal. Early failures of the Drawtite hitch discovered this the hard way. The response was to add a fore-aft member to stop the 'twisting' of the bodywork when you do use those holes."There is no sheet metal in a Unibody design. see:
http://books.google.com/books?id=mNI...l=en#PPA320,M1 </p>"...The horizontal shock struts for the bumper are attached to longitudinal box sections, one per side. The OEM hitch replaces those struts with carrier braces that transfer the load into the strongest part of the unibody. It isn't a frame, but it is the nearest thing the X5 has."There is no 'strongest' part of the unibody, that's why it's called a unibody.The center 'pillar' of the non-OEM attaches to the subframe crossmember.Technically, a triangular configuration is achieved, whereas a box configuration is achieved with OEM.</p></p>