I know this is more of a lens question and might be seen in the lens forum, but I want people that have used either of these lenses for sports to answer this question.
I what to use one of these lenses on my 40D for under the basket type shots while shooting my son's MS Bball games.
I have tried renting the Canon f1.4 and had some mixed results with it. Was it me, the lighting or the lens? I'm still not sure of that one. But what I'm worried about with the Canon 50 f1.4 is the fact that it's not a true ring type USM. Is it fast enough to the focus and will it stand up to a lot of use? I have heard that the Micro USM in this lens is subject to a fair amount of failures. Research here on POTN shows a lot of these lenses get sent back to Canon for motor service and/or replacement. I like my lenses to last and be reliable as I'm sure a lot of us do.
The other lens being considered is the Sigma 50 f1.4 HSM. Anyone out there use this one for indoor sports? How fast is the focusing on this lens? Is it up to the task of following a bunch of MS kids while playing Bball?
I have done some research on this lens and there are a fair amount of people who have this lens, but have also had to send it into Sigma to be properly calibrated before it produced sharp images. That sounds like a real PITA to me. And the Sigma costs a bit more than the Canon, but if it's fast to the focus and longer lasting than the Canon, then that's what I want. I just hate when you buy something and then have to send it back to the manufacture so that it works correctly!
Sigma 50mm f1.4 - $499 ish
Canon 50mm f1.4 - $350 to $375 though I found a refurbished Canon 50 f1.4 at a reputable dealer for $334.
So, what would you do? I want either lens for more than baseline basketball, but that's what it would get used for first. That and maybe some artsy, creamy focus stuff.

