It is one the first things that I do after Windows updates on a clean install. It is not the difference between night and day but things feel more "snappy", especially on older low resource legacy machines.
It just saves a whole bunch of time fiddling around doing each change individually when a single click does it all, remember to do a registry backup first.
I also take a disk image after a clean install/ updates/ simple system tweaker, it gives me a known good clean point to go back to in the event of total disaster and I can be back up and running in minutes.