Headgaskets any worse than all the other vendors just because its price? Its genuine oem. As far as the injector kit. Ive installed all 3 and when installing the jwt I noticed without the cap the injector would slowly rise from the rail, as opposed to the czp kit in which the injector sat in place and didnt separate from the rail. Both products do their job correctly as long as the o-rings and o-ring mating surfaces are lubricated properly.