Autofocus and iris control always works.
The only drawback that I noticed is that he rules a little play between the camera and adapter, so you always have the feeling he would not sit right. It does not affect the function but is simply not such a good feeling when the lens towards the camera can always twist a little. It is about 1 mm - 2 mm play with my adapter available.
Otherwise a really good and cheap substitute for usable only at certain Canon lenses house's own converters.
