It compares specifications and features, pros and cons of each, and also IQ aspects from the DxOMarks. So, here we go, for a few examples:-K-5 Vs 600D: http://snapsort.com/compare/Canon-600d-vs-Pentax_K-5K-5 Vs D7000: http://snapsort.com/compare/Nikon_D7000-vs-Pentax_K-5K-5 Vs K-r: http://snapsort.com/compare/Pentax_K-5-vs-Pentax_K-rK-5 Vs 5DII: http://snapsort.com/compare/
