I would think accuracy of the light has more to do with the brand and the age of the equipment. I bet you could verify the accuracy pretty quickly by running it in comparison with a light that doesn't have the fancy adjustment. Shoot a gasser engine with the degree scale with the low tech light and read the number. Then connect the hight tech and zero out the light on the scale by moving the knob. Read the dial and see what you get between the two.Or am I messed up on this?
If you know your timing advance curve is correct then it is totally helpful to set the static timing.
I've found the pulse adaptor does not work very well past 1500rpm, and even.... you need to take into consideration the load on your pump when you check the timing, it's impossible to do at neutral, you have to drive the car at various rpm and load.