Today I bought an open box Panasonic DO-UB820-K to replace my Sony UBP x700 which froze randomly with different discs. Movies started up faster and didnt freeze. Watched a little Interstellar and messed with the HDR optimizer, then Godzilla vs King Kong. That has great picture quality and sound. Since getting an Atmos setup and now this player, I want to rewatch my whole 4K collection.