I'm replacing chains on a number of bicycles, and trying to decide what chains to purchase. I'm a fan of Sram's master links, so I'm comparing the Sram PC-971 to the PC-991. The PC-991 is considerably more expensive, but it seems like the lighter weight chain would make a significant difference in pedaling performance, because of the angular momentum involved. Are my instincts correct, or is this just a sales gimmick on Sram's part?
Also, I've seen some reviews indicating that the hollow-link chains are prone to breakage -- is this something I should be concerned about?