I got this lens with some trepidation, as I haven't been able to find much solid information about it on the web, in particular, tests with examples. Opinions seem to range from very positive to very negative. I wanted, however, to have a wider lens than my 35/1.4, and this was one of the few choices -- apart from the 14/2.8 the only "L" choice. I did find one Chinese language site (search Google images for EF 24/1.4; only a couple pages come up) which compared the 24/1.4 and the 24/2.8, and a table from Chasseurs d'Images which compared sharpness between them. What I gathered from those links is that the 24/1.4 is much better color corrected but slightly less sharp than its smaller brother. OK, I figured I wanted the build quality and the extra speed (it's hard to throw things out of focus with wider lenses and having the 1.4 makes a lot of difference), but I worried about sample variation. So I was prepared to send one or two examples back if they weren't as good as the minimum that I'd expected.
I was very pleased, then, to find that the sample of the 24/1.4 that I got was at least as sharp, if not more sharp, than my 35/1.4. Its color is right on and its build quality excellent, just as expected. But the bonus is the lens' sharpness. In the center it's very usable at 1.4; by f/4 it's extremely sharp in the center and quite good out to the corners. Its overall personality is very pleasing.
I can recommend this lens without hesitation.