I just tried the 25mm T1,5 cine version, and i was really satisfied with that one. The build the price, the picture it can make.
Yes it has no eletronics in it, and the focus ring is designed for movie-like slow but steady moves, so its a bit harder (but fluent!) to turn, than a regular photo lens.
In a fast/random changing situations i would miss the lack of autofocus, since its hard to keep in focus, especially for someone with no experience, but other cases i wouldnt think its a problem.
One more thing: of course the camerabody (5dmkIII too) couldnt communicate with the non-existing aperture motor, it asked for verifying if there is any lens attached every time i turned it on again. Not a big issue eithet.