Disclaimer: I do not own Saint Seiya characters. Saint Seiya is the creation of Masami Kurumada
Mu or Shura
When Mu and Shura were still kids:
Mu: "How come you say that Excalibur is better than Crystal Wall? Crystal Wall can deny any attacks. You see, I can make you sure that Aphrodite will end to a floral garden himself and Saga will be sent to Another Dimension if they dare to attack my Crystal Wall."
Shura: "My Excalibur can chop the enemy into 23 parts in only a second. And don't forget, it also has multiple utility. I can give you various haircuts with that."
Mu: "My Crystal Wall can be used to practice tennis."
Shura: "I can make gardening and cooking faster with my Excalibur."
Mu: "…"
Shura: "Hah! You lost, Mu!"
Mu: "Let's see…your Excalibur is useful for daily activities, but it doesn't help much in battles."
Shura: "What…?!"
Mu: "Yes. Just admit that in battles, Crystal Wall is more useful."
Shura: "Aaarrgh…mine is more useful!"
Mu: "Mine!"
Shura: "Mine!"
Mu: "Mine!"
Shura: (launched attack) "Excalibur!!"
Mu: "Crystal Wall!!"
Shura: (fainted) "AAAARGGH! I'm torn into 23 pieces!!"
Mu: (sighed) "Don't worry, Shura, I will fix and repair you."
So decide yourself whose skill is more useful. :D