I put the ESH chain on my track bike this winter, after using the original KMC K-5A chain for 4 years. Although the KMC never stretched very much, it was always extremely noisy and seemed to create excessive drag, especially on a 13T cog. The ESH is much quieter and smoother. One thing I noticed when I removed the KMC chain was that the inner links lacked a connecting bushing, but instead the link plates were pressed inward at the pin holes to form a bushing around the pin. This seems like a very crude and cheap way to form the links and may account for the rough operation. I also like the fact that the ESH chain uses a bolted connection instead of a masterlink. My old school steel track bike (Paramount P14) has a Reynold chain than has lasted for eons and is very quiet.