I actually prefer the American reasoning but 'are' is still OK in both cases because you can substitute "Angels & Airwaves" by 'singular they'. E.g. "Angels & A

I actually prefer the American reasoning but 'are' is still OK in both cases because you can substitute "Angels & Airwaves" by 'singular they'. E.g. "Angels & Airwaves is a band. Some would say that they are a great band." or "The editor became frustrated because they could not understand the logic".