My road bike came with mostly 105 10-speed drivetrain, but I'm not sure if the chain was Shimano 105 10-sp or not. Anyway, after about 2,000 miles it had nearly 1/8" of stretch in 12 links, checked with a metal ruler. I swapped it for a KMC X10L-Ti gold chain and Ultegra 10-sp cassette, and it still has no discernible stretch after over 5K miles.