Ah, OK.
Another tip that you can try is to have your Activity Monitor open. When the mouse lags, check the CPU usage in the Activity Monitor. You may find out the mouse is not the problem, but just a result of something else taking over the CPU for a few seconds (I'm assuming the ~5 means seconds or minutes, and not hours 😀 ) Could also be that your Mac is sometimes running low on memory, and a slow mouse would be one result. It's possible that you can address that issue, and everything else may improve.