Spartan martial prowess wasn't anymore effective, individually or as a group than any other group of their time. Eating beef and raping slaves is simply not good enough reason to persist this mythology.
Carthaginian sacred band had better equipment, fitness, tactics and discipline, combined with a religious zeal that made their morale unbreakable. They also ate meat, whatever that's worth. Apart from a single dubious and assuredly propagandized solo account from well known liar in history, Sparta simply has no consistent feats to backup any of the mythology that has been popularized by comic books and movies.
By off chance, did you mean the Thebian Sacred Band? Since they did beat the Spartans, whereas the Carthaginian Sacred Band was a different era, and while known for being "elite" by we know them best by two defeats they suffered.
Carthaginian sacred band had better equipment, fitness, tactics and discipline, combined with a religious zeal that made their morale unbreakable. They also ate meat, whatever that's worth. Apart from a single dubious and assuredly propagandized solo account from well known liar in history, Sparta simply has no consistent feats to backup any of the mythology that has been popularized by comic books and movies.