This is one of the few "SDM Only" lenses with a "KAF3" lens mount, but its reliability is still in question for a long time since marketed, for a long time already. Here is yet a latest user report on the AF (SDM) failure of the lens:-http://forums.dpreview.com/forums/readflat.asp?forum=1036&thread=36075191In fact, there have been quite a number of previous failure reports, by different users/
