Well, I'm on the fence on this Sigma 1.4 Art. I have all but a 50 prime in my bag already.
8-15L, 16-35L, 24-70 2.8L Mk 2, 24-105L, 70-200 2.8L Mk 2, 35L, 85L, 100L Macro, 135 2L.
I didn't care for the 50 1.2 and sold my 50 1.4 years ago. For that focal range, I just used my zoom (24-70 MkII). I think I am chasing the sharpest lens dream and really don't need this thing. The images people are posting look pretty good, but the complaints about having to adjust them is troubling. All L glass so far, but recent Sigmas are peeking my interest. I'm debating on skipping a 50 altogether and getting a 100-400 to capture my kid playing softball. For lacrosse my 70-200 was awesome, but my daughter is outfield and cropping the images later still gets a little grainy for my liking. I thing the 400 would help a lot. I had the 2x extender for the 70-200 and didn't like that either. Maybe I didn't give it enough of a test. I sold it on EBay for 20 buck under what I spent on it. Thoughts? try the 1.4 ex or get a 100-400. With my luck I will get the 100-400 and Canon and/or Sigma will make a newer version...LOL Happened with my 35L. I got it and 3 weeks later they released the Sigma 35.