When I decided to go digital, I was looking at Canon and Nikon. It was suggested on another camera forum to take a look at Pentax, since I had an old Spotmatic. To tell the truth, I had forgotten to look at Pentax since all the advertising was toward C&N. With the in body image stabilization and availability of old glass, coupled with being able to go into an old camera shop and actually compare all 3, I choose Pentax. I also choose Pentax knowing full well that once I purchased into the system, I would probably never change - just too cost prohibitive - for a hobby. It was a conscious decision. That was the K100.
I have gone through the K20 and now the K5, each mail ordered sight unseen. What does help is that that I move about every other model and only at the end. The model is debugged, and shaken out by then, and the price has dropped by at least 40+%. Not an early adopter by any means. Having 12 to 18 months of reports also helps.
So, do I really "need" anything else? Not really. The K5 is an astonishing system. I can understand the need for a FF by others, however this is just fine for me. I really do not understand a lot of folks changing from Canon to Nikon, and back again, then to ..... In my mind it makes little sense, especially if you are not a professional.