As a follow-up to the recent cordovan thread, how much of Sea Island Cotton is legend versus reality? Has it become just a marketing term? Is it worth the extra cost? If there's an advantage, is it comfort, durability, or appearance? Is it better suited for one class of garments such as shirts, sweathers, or socks; or are its advantages, if any, across the board? Does the quality of SIC vary from vendor to vendor, or is pretty consistent?