8,10,12 or 14 bit rate doesn't change the dynamic range of a camera. The dynamic range is limited to what the sensor is capable of and the preset curve of the picture profile. Color depth of course is different BUT when shooting 4k for 1080 export the extra pixels contain enough color info to create a true 10bit 444 file. So in essence increasing bitrate to remove the occurence of macroblocking in shadows and at higher iso's is significantly more beneficial.