I've been participating in the mirror flopping issue, EVEN THOUGH my camera does not have it. And i'm not the only one. At this point, i'm just curious, like you, of what else is out there.
After reading too many posts about the subject, it sounds like an electronics problem with probably a small batch of some electrical component that doesn't work well when the battery is fully charged.
Total number of people who have reported it is about a dozen i'd guess, didn't count. Thats a very small number, except if you're one of the ones that have the problem. I no longer am concerned about it. Pentax will figure out which circuit board the component is on and it will become a standard repair for those that experience it. My camera did not have a stain, focus problem, etc. so maybe i'm due for it
.
If we start hearing about hundreds of cameras in the next 2 months, then its a bigger problem, right now - not.
Meantime i'm going to enjoy the camera, still having fun with it.