I honestly think it's a terrible combination, but I have to admit that it's a win-win for all concerned.
AC/DC can now complete the last two dozen or so concert dates they had committed to before Brian Johnson stepped down. AC/DC rarely have trouble selling tickets wherever they go, but I'm sure that having someone of Axl Rose's caliber taking his place will draw out the curiosity seekers and virtually guarantees that all of the shows will sell out. I wouldn't be surprised if at least one of the concerts is taped for a live album/DVD while they're at it.
As for Axl, he is preparing to go on a stadium tour of his own with the reunited Guns N Roses, so performing these AC/DC shows are the perfect way to get him back into road/touring shape. AC/DC are known to run a notoriously tight ship so Axl's trademark onstage melt downs, showing up two hours late, etc. will not be tolerated. For all we know, these could turn out to be the best live performances of Axl's career!!