Russell Evans, member of the DPR Pentax forum, has compile a loooongish list and summary for *some* of the failure reports at the DPR that he has searched:-
http://forums.dpreview.com/forums/read.asp?forum=1036&message=33859084
Great Job, Russell! I have to say..
Well, this issue is actually a common one, which has been widely reported now since the first DA*16-50 was launched years ago, and various different lens models with SDM are affected up till now.
In fact, I think Pentax/Hoya should look (have done already?) into the problem and offer a free product recall for all the problematic items as such. (if they already had a solution! IF Only!)
Besides, if you want to look at those Pentax gear issue reports by different Pentax users, DPR is still the best place to find them (you will find many of the reports and issue reports have been coming up earlier too). Ironically, whilst now the PentaxForums.com also has many Pentaxians as "members", the people who run the site have set up a very good human filtering system over there so that such "Negative" user reports are not encouraged, here is an recent example, that is moved from the DSLR Section to the "Beginner's Corner"! Funny enough? See:-
http://www.pentaxforums.com/forums/pentax-dslr-discussion/81942-k20d-underexposing.html
(It will be redirected, since it was moved.)
Update (12-4): One more example, which has just happened today:-
http://www.pentaxforums.com/forums/pentax-dslr-discussion/82219-k-10d-lost-images.html
(It will be redirected.)
Well, does the PF has implemented an "automatic thread/post moving function" once any poster types in the word "issue" and asking for any question related to gear problems? Wow, that must be great! Lol..
Last Related Post: SDM Issue Strikes Again - This Time DA 17-70