How much improvement with better toslink cable?

Tos-link or Toshiba Link is every bit as good as spdif over wire IF and only IF you use a glass cable, It makes a HUGE difference. I used a plastic Tos into my Museatex Bidat and it sounded really bad (actually multiple plastic toslink cables) and then I purchased a Monarchy Audio glass Tos for $50, well let me tell you it is the ONLY digital interconnect (and their have been MANY down through the years from $300 to $2000) that matched my FIM digital spdif cable. When people say they can't hear the difference, I of course believe them, but that doesn't mean you wont hear it... it AINT (improper grammar for effect) subtle :) You needn't spend a lot, but the worst connection you can possibly have is a plastic toslink. Trust me, it is not the interface it is the medium. A lot of people are not aware that plastic was used in industry with AT&T st-optical but it was far inferior to the glass....same thing with toslink. Mine sounds remarkable and like I said, in direct comparison to the best wire based digital cable I know of.