agreed that would be awesome for basketball, I'm often switching between my 50 1.8 and tokina 80-200 f/2.8, I find the 50's aperture to be wide enough that I can stop down a bit, or decrease ISO and still get a properly exposed shot, and the 80-200 f/2.8 to be a bit slow aperture-wise to get a properly exposed shot without a high ISO, so a 50-something 2.0 would be awesome, however If it was more along the lines of the tokina 50-135 but with the constant 2.0 that'd probably be my Ideal basketball lens, long enough that you can get the other end of the court and wide enough that you can get your end as well.