Assuming I can find an equivalently desirable icon here, in font awesome, or an SVG; which should I prefer?
The shortcoming is that you can't do any icon in the world with css. But if you already find this is equivalently appearance wise, the performance and code hygiene is much better than SVG or icon fonts.
also icon fonts are the worst way to do icon, here is the article about why: https://github.com/blog/2112-delivering-octicons-with-svg