Originally posted by WerTicus You get what you pay for. The raw bit depth is everything when it comes to the final image quality.
Are you sure about that?
12bit vs 14bit RAW and compressed vs uncompressed… Does it matter? | francoisMalan
Looks like the extra depth is mostly visible on the ends (highlights and shadows) thus largely negligible UNLESS you are shooting in tough conditions (bright light and dark shadows in the same scene) or are under/over exposing by large margins.
Actually the only things that would steer me towards a K-5 mk2 would be if I needed the mag alloy body, the mic jack, or the battery grip.. from a 'real world' point of view. I have a K-30 and would benefit from the battery grip largely and perhaps the mic jack lightly.
I guess the burst mode is technically faster too by a frame per second on the K-5 series and the low light focusing is supposedly improved. So take those into consideration as well.
Ok I also left out the feel of the camera. This is important as you will be taking most of your photos (likely) with your camera firmly in your hands. This means the camera needs to feel right in your hands!
Therefore, If you have the ability to handle each, I'd recommend you do just that.
Oh, and the K-5 mk 3 will likely be out a couple of months after you buy whatever you buy.. thus 'obsoleting' it's newness to the product lineup... enjoy.