I’ve long preferred a mix of ems rems (and percentages for that matter) over pixels in web design and front-end development. However, some of the original reasons have gone away as browsers have gotten smarter.
Yet, Vasilis van Gemert has collected some thoughts and links on why it’s still good to utilize ems and rems over pixels. Front-end nerds can get lose in Vasilis’ links for a while.
Enjoy and feel free to send me hate mail. But for real, the 62.5% “antipattern” is seriously the worst.