I'm not so sure about glossy tire products. I used to like them since it has that "cool" factor when you have wet lookin tires. But then there was that idiot in the Lexus IS that put it on the treads and slipped into a tree.
. So that got me thinking: if I truly corner that hard, do I want any kind of "slippery substance" anywhere near the tread? I do corner hard enough where I can see wear marks on the outer 1" of the sidewall. Maybe its paranoia, but I swear that shiny stuff leads to less-than-ideal at the limit handling.