Currently, I am not receiving any slow down and haven't for a very long time. My internet is through our cable provider (2G and 5G). Although, during stormy weather, it gets a little crazy.
At my previous QTH (Ash Fork, AZ - South of the Grand Canyon), I would get slow downs from time to time. But that was mostly due to my internet connection, not Eham. Then, I only had a DSL connection and that was routed 50 miles west to Flagstaff and then 150 miles south to the Phoenix main hub.
Every so often we would have an outage for a few days. We had some "goobers" in our area that thought they would get rich by digging up the cable that ran from Flagstaff to Phoenix. They would sneak out to the desert and dig it up. But when they cut into it, they found out it was fiber optic cable, not copper.