Last summer, I brought both my K1 with a DFA 28-105 and my 645Z with an FA 45-85 mm to Arizona and Southern California. I'm getting older and both of my knees have been replaced so I walk with a lot of difficulty. I used the 645Z only close to my vehicle because of its weight whereas I walked much more easily with the K1. I adjusted my color palette to "Vibrant" on JPEG capture for both cameras. My images look much more "static" with the 645Z and much more "spontaneous" on the K1. I tend to agonize on composing my pictures with the 645Z, seeking perfection, but this tends to cripple the naturalness of the final images. I ended up preferring the K1 images, though technically speaking the 645Z is much superior. The picture of the Grand Canyon above was taken with the 645Z. The picture below was taken with the K1 after a long walk in Petrified Forest Nat'l Park, handheld with a CPL.