1. This K-5 user reported a tilted viewfinder:-
http://www.dchome.net/viewthread.php?tid=1074731&extra=page%3D1
He said that using LiveView was okay and he was able to get perfectly levelled pictures. But however, with the optical viewfinder, the final pictures were always inclined.
2. This O-GPS1 and K-5 user found a bug on the calculated maximum tracking time limit in the astrotracer mode which is much shorter practically with his telephone lens attached and thus tracing failure was resulted and the errors are shown in photos:-
http://forums.dpreview.com/forums/readflat.asp?forum=1036&thread=39556416
3. This user's K-5 unit should be defective as the camera just won't shoot when the built-in flash is popped up. But the first responder to the OP pointed out an earlier firmware bug about the conflict between the LiveView and the pop-up flash that would cause exactly the same lock-up. He claimed that the latest K-5 firmware has resolved the problem, though:-
http://forums.dpreview.com/forums/readflat.asp?forum=1036&thread=39558544
4. This FA31 Limited had the light-sealing rubber inside the front glass detached, for two positions. The user said that the lens has been used for five years but it has never been mistreated and actually great care has always been taken for use and handling. The lens has also been put in electronic cabinet of his when not in use, with the relative humidity set at 40 to 55%:-
http://forum.xitek.com/showthread.php?threadid=924645
(in Chinese, English Here (machine-translated))
A photo of the found defects is also attached.