Cameras with more dynamic range allow you to take photos with dramatic differences in highlight and shadow areas while retaining detail in both.
Think of a brilliant sunset on a rocky beach: Bright sunset in the background, with dark rocks in the foreground. High dynamic range means more of the extremes will be faithfully reproduced.
Dynamic range test data courtesy of DxO Mark.GX85 test data on DxO Mark GH2 test data on DxO Mark
Excellent build-quality; Good ergonomics for its size; Built-in 5-axis Dual IS, Built-in EVF; Tilting LCD touchscreen monitor; Competitive still image quality; Excellent 4K video quality; Fast autofocus and burst modes; Generous buffers; Tons of advanced features; Built-in Wi-Fi.
EVF could be better; Sluggish RAW and RAW+JPEG buffer clearing; No external mic and headphone jacks; Slow x-sync speed; Mediocre battery life.