The bushes also came with cast channels for it to run or you'd end up with a blob on top and oozing out the sides and nowhere else. It's more for if squeaking is a constant issue, which is probably why they were also trying new variations with the fibre lining. That was a few years ago, maybe have something else now.
I just checked, my firebird has the grease fittings front and rear so it must be one of my others that had the inner lining instead - yes, found pics of Whiteline bushes on my other car with the fuzzy insides. Either way, just variations of the same theme to stops noise. Looks like the ES bushes are still plain or greasible, here's a random pic showing both bushes from other brands.
https://www.suspension.com/blog/wp-content/uploads/2015/08/swaybarbushings.pngBe aware that not all bushes will fit your stock, or whatever you have now, mounts. So a safer bet would be one that comes with both. They are often slotted to fit universally, or use a round file on one end until snug.
