If you couldn't have fun on the way down, what would be the purpose of climbing up?
Seriously though. Even though I enjoy 40+ downhills, I only do that on hills that I am familiar with (road surface, gas pipe placement, manhole covers etc) and I prefer back roads with no traffic for that.
Fortunately most of my riding is off pavement and I almost never get over 30. My wife and doctor both say its bad for my blood pressure....
