I think Rapid Strike Urshifu is the better Kubfu evolution compared to Single Strike Urshifu. Firstly, it has better typing coverage, as it has more defensive resistances. Although it has five weaknesses, Single Strike Urshifu is extremely weak to Fairy-type moves, receiving x4 damage. Although it can get walled at by defensive Pokémon like Toxapex, a simple U-turn can do the trick.