From the quality standpoint both of these lenses are going to deliver sharp images with good bokeh. They're both Canon primes with a great F stop. And my guess is that either can deliver sharper pics than just about any zoom lens out there -- L or not.

The real issue then, which lens does the job you want done, a 35mm or a 50mm? If it was me, I'd probably go with the 50mm even if the price was the same. The 50 is closer to how your eye sees the world and it's a great lens for portraits, walking around, etc. The 35mm is closer to a wide angle lens and for that range, I usually grab a wide angle zoom that gives me more flexibility. But you have to ask yourself what kinds of requirements you will have for the lens.

Plus of course, the 50mm is what, a third the price? For what you'd save on the 50, you could also get the excellent Sigma 30mm 1.4, one of the best lenses out there.