@font-face, Javascript vs CSS

I'm wondering if anyone 开发者_Python百科has had any experience comparing the performance of @font-face fonts from a font service that requires referencing via Javascript ( such as typekit ) vs. a font service that requires referencing via CSS ( fontdeck ).

Thanks!

---

Since they both have to use CSS, obviously adding JavaScript to it can only make the process take more time (CETERIS PARIBVS).