Getting rid of the single shaft doesn't fix geometry. It just allows stand adjustability, which can aid in correcting geometry, and that is provided the rocker is designed right. Figure in the machining of the heads, and the lifter bore bushings to pushrod oil, and combine that with the increased cost of the paired (still a shaft) rocker system, and you are going to drop some serious coin for that upgrade. Don't get me wrong, it's a nice system, but the only advantage it has over a proper single shaft set up is the ability to remove /install one pair of rockers at a time. Is it worth the added expense for most folks for the added convenience? Only they can make that choice.