With so many great full-frame mirrorless camera options on the market today, it is becoming harder and harder to understand their differences. Almost every major camera brand now offers a wide variety of cameras and lenses at similar price points. In this article, we will compare high-resolution mirrorless cameras in the $3-$4K range, namely the Canon EOS R5, Nikon Z7, Panasonic S1R, and Sony A7R IV. We will take a look at three key factors. First, we will take a look at the ergonomics of these cameras. Next, we will look at their specifications side-by-side. And lastly, we will take a look at each system as a whole and compare their lens options.