I've never been on a Speed, but I used to own a Mu SL. People say the frame is much stiffer on the Mu, and I believe them...it was a very stiff bike. Dahon has hinge problems and stem problems, but they do a great job of providng a light bike at a low cost. The Mu SL is a 9-speed, though, as you probably know.

The suspension hub doesn't seem to do much, and the ride is indeed a bit harsh. I agree with the above comments. The bikes strength is its ability to quickly fold into a small package. I think the Dahons are second probably only to the Tikt in terms of time and ease of fold.

If you want a quality performance bike that avoids the hinge but still folds small, there's the (expensive) Birdy. Today, I rode with another biker on a 10-year-old Birdy that has been ridden nearly every day over that period. That probably won't happen on a Speed; the frame hinge and stem probably won't make it that long. If you don't need the folded package to be small, Friday.