Raced the Gran Fondo Frank Schleck in luxembourg as a UCI Worlds qualifier. The level in these events is generally very high, Winner ended up with a 25+ mph average over a 100 mile reasonably climby course. Just be prepared for massive peloton action and the craziness that ensues from that. rolling 28+ mph in a 400 man bunch was pretty damn sketchy.
Great fun though, especially while you can hang onto the front bunch.