What this world really needs is yet another 50mil.. Don't think so, SamJunk is smarter than that.
Actually, the world does need a modern 50mm under $1,000 that's usable (for more than just portraits) at 1.4. If Sigma wasn't releasing a 50 of their own Samyang would stand to make a killing if it performs good wide open (i.e. on the same level as their 35mm and 85mm).
I haven't noticed that shots from my EF 50/1.4 were unusable, not on the old 5dc I got that lens for nor on 5dmk3. Nor I heard from nikonians their new G 50s weren't up to any task. Pixel-peeping amateurs might have something to complain but I still think even after so many years that EF50/1.4 is a bang for a buck lens.