rusticus: sorry - I think you do not need the K-5 II or the K-5IIs if you own the K-5:Differences are splitting hairs, not otherwise
D1N0: K5IIs is the sharpest aps-c dslr sadly it's not suited for photographing stamps and bank notes.
I'm no expert, but expect you are correct, but thankfully pentax is offering something different. I'd like the high ISO performance of the pentax, but with 24 MP. If I have to chose one I'd prefer the low light option. I'll wait and see how the Nikon 5200 does, and I'm also considering the 5D mk2. It's a great time to be a photographer.
PS. I do agree with you sentiment, there are many times when moire can be a factor, particularly hair and fabrics, but for me these are unlikely to be an issue.
colesf: The k5IIs has pretty crappy moire. What's curious is that the Canon 5D mk ii and iii both have it just as bad.
Seems that resolution may be a significant factor, the D800E doesn't suffer from moire where the K5IIs and 5D Mk2 (and MK3) do on the studio scene.
I'm considering both of them for a future purchae and found exactly the same. It doesn't help me decide, but it does make me realise moire won't be a factor in my decision.