Upload & Sell: Off
+1 - my exact experience. You shouldn't have to develop an entirely new AF system in order to even remotely have a remotely reliable lens. I can't believe people defend this lens in light of it only f***ing working somewhat properly on the 5D3 and 1Dx.
To be honest, for all of the crap I have heard about the 35 arts low light focusing problems, it probably still focuses more accurately, precisely, and reliably than the 50L.
It works good on my 1D3, 1Ds3, 1D4, 1DX & 100D bodies. And before that it also worked good on my 10D, 5D,1D2 & 1D2N