This is a great little lens, I know mine doesn't get much use anymore but I've always got a soft-spot for it. First fast prime (as I'm sure it was for a lot of people), but not only that, despite all my more expensive lenses, a photo from this lens got on the cover of a book:
Just got this lens a few weeks ago.. and took it to a couple of basketball games. Over all I think it does quite well inside the gyms. I am still learning on how best to use it though to get more shots in focus.
This is my favorite lens which would be my most favorite lens when I get the 6D. Currently, it's the 28mm F1.8 due to the crop factor but I expect that this will be very much used when I get the 6D. I love this lens for portraits on an APS-C. If you can't get excellent shots from this lens, then you've got a problem. No one can ever blame this lens for taking the best pictures even at the least price.