Get rid of K-7 is a good idea
. I used to upgrade from K-x to K-7 and the result sucks ^_^. I ended up went to Nikon. It is quite painful to get rid of whole pentax kit and switch. It took me several month. Man it is quite painful. Now it is impossible for me to switch back since I acquired some Nikon legacy glasses and satisfied with the optics.. Since you already get so many top quality pentax lens, just stay with pentax. I think any pentax DSLR after K-7 is superb to K-7. Samsung sensor did ruined some reputation of pentax from me.
But one temping alternative is the sony nex. Sony seems don't care about it's own DSLR line. Sony only wants the camera business. So we have the opportunity to enjoy the pentax lenses and best sensor that sony made altogether
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