Undoubtedly, 4K is better than 120 fps. For one, the resolution is significantly higher in 4K. This means that you'll be able to see more detail and clarity in your video footage. Not to mention, the colors will be more vibrant and true-to-life. Secondly, the frame rate is also doubled with 4K footage compared to 1080p footage shot at 60 fps. This makes for smoother, more lifelike video playback. Finally, with 4K you also have the option of downscaling to lower resolutions like 1080p or 720p without losing any quality, which can come in handy if you need to conserve storage space or don't have a powerful enough graphics card to play back 4K