oh boy ... during the time of reading this thread i´m starting to get worried about if it was worth buying this lens. I got my one march of this year. While using it for several weeks the AF refused "hitting" more often. Now i have to correct AF by internal AF Correction at +10 and at least the lens is hitting again.
Have to bring it to our local Pentax Repair Service in Hamburg, Germany to fix it. I´m really disappointed about the quality of this lens by considering the price (nearly 1000 €)
At least i have still warranty on this lens...