I'm definitely all ears about your experiences with the camera, especially seeing as you use an EM5II as well, like me. You must find value in the big ol' K-1!
This camera really never got much of any representation on Cameraderie for some reason.
Not surprising that the K1 isn't represented here much. It isn't represented anywhere much. It is a pretty niche camera from a niche brand. Which is too bad, because it really can give outstanding results.
After a big western road trip a couple years back in which I shot solely with the E-m5ii, I came away a tad disappointed. Don't get me wrong, I love using mft and can get great results with the system. I just felt that there was a bit missing from many of my images. Mainly the DR and resolution seemed to be the limiting factor in PP final images. I had finally gotten to the point where I wanted a bit more. Also, my E-m5ii took a tumble in Arches that broke the plastic around the hinge. Unfortunately, I no longer consider it weather sealed.
So I began looking at the options available. I could have upgraded to a 20mp mft body. I was really leaning that way. I had tried a Fuji (X-E2) previously. Nice images, but APSC didn't seem enough over mft. I had my Leica R glass that I really wanted to take advantage of the full image circle. I briefly had a Sony A7ii. I just didn't like the handling of the Sony. Canon and Nikon FF mirrorless was outside of my price range.
That lead me to the K1. Then looking at the specs really piqued my interest - FF, IBIS, industry leading weather sealing, GPS, Astrotracer, Pixel shift, creative multi-exposure modes, capability for all Kmount lenses, and more. It really has a lot of technology and several unique features not found elsewhere. The downside - it's a heavy hunk of metal and plastic, and its a DSLR. The latter of which has been the biggest hurdle for me. The OVF is finally growing on me.
After ~18 months, I have to say that the K1 really has fulfilled the role that I wanted it to in my kit. I barely use the E-m5ii any longer, unfortunately. Though when funds allow, I will probably upgrade my mft gear to wildlife shooting. That is really the biggest weakness of the K1 for me. It would be nice to have more reach. To do that on the K1 means really huge lenses. The 2x factor of mft just makes it much easier to get reach.
I am really pleased with the results of the K1. It is capable of some results that I would have had a harder time with on mft. And I have had a bit more success with its results. I had a photo on display at a gallery last summer and I just had another one picked up for display in June. The way I look at it is that the K1 isn't necessarily a better camera it simply increases the envelope of capability over mft in the ways that I was looking to work. I think it makes for a really good complimentary system to mft.