So which camera would be better coming from a Nikon body. I have plenty of Takumar lens to hold me over until I can get a new Pentax lens. From what I understand the K-3 is having problems with the shutter. I don't know if a firmware update has fixed this yet but if the K-3 is worth it then I would get it. However the K-5IIs doesn't seems that much different and is about half the price. Some say the K-5IIs performs better than the newer body.
I've been trying to decide on a camera body also. I've looked at different models from different companies but I'm more drawn to Pentax than the others. At one point I was leaning towards Canon, then Nikon, and then back to Pentax. Pentax systems offer great value, fantastic IQ, great color saturation, contrast, good AF, and more fps than I really need. Weather sealing is a major plus for me, too. Trying to decide which body to purchase shouldn't be this difficult. The K-5 IIs and the K-3 are both great cameras, but I drool over the new K-3. However, the K-5 IIs is like half the price and still better than many more expensive cameras. I've seen great images produced by both bodies, and frankly I'm not sure the K-3 is going to offer much better IQ than the K-5 IIs. Sure, it's more advanced, newer, has more MP's, and is a bit faster, but the more I think about it ... the K-5 IIs is really more camera than I truly need. Drool factor goes to the K-3, but practicality goes to the K-5 IIs hands down! I don't think I'll ever regret buying either, but by buying the K-5 IIs I'll be saving a substantial amount of money which can be used for better glass and/or other necessary accessories. With that being said, I myself chose the K-5 IIs. It simply cannot be beat for value. I'm going to pair it with a Pentax 77 mm f/1.8 ltd lens to start me off. The 77 mm ltd is one of the three amigos/divas/princesses. Can anyone say pixie dust?

In the end, the K-5 IIs is an incredible value and I'm not sacrificing IQ by purchasing it over the K-3 ... at least not enough to sway my decision to go with the K-5 IIs.