In my experience the polymer coating on the expensive Shimano shift hables peels off and gets stuck in the ferrules. The Optislick coated cables marketed for Tiagra and 105 might be marginally better than the standard mid-grade polished stainless that most shops use in bulk. It definitely doesn't peel. For my money the midgrade polished stainless cables, by Shimano, SRAM, Bontrager, and Jagwire, are all excellent. Perhaps the housing liner by Shimano might be a little slicker.