Nothing wrong with riding fast as long you enjoy it, I got a point about a decade ago where every ride felt like it had to have a specific training purpose, aka a chore, and something in me said STOP so I stripped off my Polar computer and HRM and just rode, man that felt good, as good as going 17 mph did, and I noticed stuff on rides 1'd done dozens of times that had never registered before, has the eagles nest always been there? Not long after that I discovered lugged steel. Now that I am older and fatter its not so much of "choice" which a long way around to say do the type of riding that puts a smile on your face.