dfu4040712wrote a review of Continental Grand Prix 4000 S Tire - Clincher on September 10, 2010
Probably the best clincher I have used. It rolls very well. It doesn't feel like the fastest tire in the world, but the ride is excellent, the quality of construction is first rate, and it feels solid and durable. For me this is an excellent tire for fast club century rides. The Pro Race 3 may feel lighter with lower rolling resistance but it may be more prone to flats than the strongly built GP 4000S.
Excellent all around product.
Excellent on time delivery from RealCyclist too!