Just because you do not see a benefit does not mean there is no benefit. Logically, if you remove a program from a computer, which is always using computer cycles and other resources, then it stands to reason said computer cycles will be able to run other programs and use resources freed from terminating that program.
How much of a benefit will strictly depend on the computer and its configuration.
Superfetch has the potential of speeding up the first load of any given application and that is the end of its benefit. After the first load, the application will be cached by the Windows OS thus negating any need for superfetch.
If it is more important that a program might load faster on its first execution, than having the freed resources for any other application to use, then leave superfetch running. Simple.
However, on a resource limited computer, it would be borderline moronic to leave that process running.
If you want every cycle you can get to run a game, or any other system intense application, then disabling superfetch is a good thing.
I also disable "Themes" as it is a huge system resource hog. Disbabling it gives me better transcoding times on my videos. Just FYI. I know having all the 'pretty stuff' is important to a lot of people, so I rarely bring up disabling that service as I get there are many who would be chastised for killing off the 'pretty, fluff stuff' in Windows.