Well, if you like it on an EF camera, you'd have a near orgasmic experience with it on an R series camera... thanks to the eye AF.The 2.0 is 500gr lens! It is a bliss to use. If you want a 1.4 or 1.2 you will have to buy bigger more expensive lenses.
This to me is all I want! It is the lens that is keeping me from jumping to EOS R series.