Excellent chain for a triple crank. Has lateral flexibility and shifts well. It is the same as the Dura Ace chain for triples which was discontinued - apparently the only difference is that the 6600 is less expensive. My equivalent Dura Ace chain lasted 2500 miles to the point of 116 in. wear over 12 links. I am a heavystrong rider.
Note do not use the CN-6701 for a triple. It is laterally stiff and will wear the top two cogs of the cassette out in only a few thousand miles. It will also not shift as well on a triple due to it's stiffness.