My local cable company used to advertise 5 Mb but it typically ran between 2 to 3 Mb. At one point they bumped up the speed and for a few days I was seeing 10 to 11 Mb! I couldn't believe it. I knew it wouldn't last long and, yes, it did drop to a more realistic 6 Mb and on slow days it runs about 5 Mb. Definitely usable and I am happy with it considering there is only one cable company and one telephone company in my area which I can use.
The attached images show my typical speed and the speed I had for a few days.