You can either judge this by talent or success. Talent wise Little Mix are miles ahead of Fifth Harmony, as they are incredible singers and dancers. They have huge amount of stage presence and actually complement each other. They have tight harmonies and choreography, whereas Fifth Harmony lacks in each of those departments...

Based on success Little Mix are also ahead of Fifth Harmony... They have sold more records world wide and have just completed a second sold-out arena tour. Even if many see them as a local act because their main market it the UK, they at least sell out arenas and stadiums there, whereas Fifth Harmony doesn't.