Anthrax guitarist Scott Ian, like most fans, never wants to see his musical heroes slow down. But that's just what's happened with AC/DC and Motorhead – and Ian is not sure what to make of it.

"It was hard to watch [Motorhead frontman] Lemmy [Kilmister] at the end," Ian tells R7. "We played a whole bunch of shows with Motorhead in September of last year in the States, and then we did the Motorboat cruise with them again. And it was great to see them, but at the same time, you can't help but think, 'Lemmy really – he shouldn't be on stage anymore. He's having a hard time.'"

Of course, Ian realizes that this was just the way Lemmy wanted to live out his days – and "you can't argue," he says. "No one was forcing him to play shows. He wanted to be on stage; that was his life. But as a fan, you know, you just can't help but think, 'Goddamn, he should just go home and play the f–ing slot machines and just relax for a few years now. He's worked hard enough.' But that's what he loved to do."

AC/DC, meanwhile, is trying to move forward after postponing a string of U.S. dates in the wake of hearing problems for singer Brian Johnson. They've said they will likely make up the dates with a replacement singer, an announcement that was followed by widespread speculation that Guns N' Roses frontman Axl Rose would take over.

"My personal opinion is, without Brian at this point, I think they should just stop," Ian says. "Why? Why? You're AC/DC. I don't think they need the money. It would be pretty hard to imagine that they still are out there working because they need money. But who am I to say? It's just my opinion. But I wish – If Brian is done, then I wish the band would stop."

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