I have messed around with several aiming systems, and they do work. However, they are only one part of the puzzle. And, will not make a great player out of anyone by themselves.
I liken it to a race car. You want the car to go faster. You take out the 150 h.p. motor, and put in a 500 h.p. motor. It will go faster for a little bit, but just changing the motor won't work. You also need to change the transmission, and the rear end. You won't get maximum results until you fix ALL the parts. They have to work in synchronization to get max results.
Independently, each improvement helps a little. But you only see real and long lasting results when you make the various parts work together properly.
Aiming is only one part.