I've got the Lens Align Lite system. It's quite good and removes the major causes of testing error. It uses a mirror to make sure you are properly aligned with the target. The AF target is good and meets Nikon specs. And it has an angled scale so you can focus on the target and inspect the scale to understand any focus error.
The AF adjustment and Lens Align system is best for longer prime lenses. With zooms you need to picka single focal length. Most zooms and shorter lenses don't need a focus adjustment. 99% of reported focus errors are most likely testing errors rather than focus errors. And the other thing to keep in mind is that both camera and lens can be off - so a focus error may be the camera, the lens, or the combination of the two.