Honestly, I'm not the right person to ask about this matter. Despite my love for Batman, I really don't care about a Batman/Superman film. I hated Man of Steel, and even Christopher Nolan's touch couldn't save it. The Dark Knight trilogy is fantastic but it has become obvious now that those films will have nothing to do with the new film. And unless Warner Bros. suddenly announced that Affleck was also directing this film, I still am only mildly interested. There's just no way that anything Snyder does with the character will top what Nolan did. Unless Snyder goes back and does something a bit more comically zany, similar to the Burton films, I don't see this being interesting. Plus, he already set the tone for DC's future films with Man of Steel, an insanely dark take on the hero.
Anyways, despite my overall disinterest in a new Batman, I don't like Ben Affleck as Batman, and it is not because I don't think that he's a great fit for the role. I think that he'll be fine as Batman, and I think that he'll do fine as Bruce Wayne. I thought that his performance was the only slight knock on Argo, a film that I still would put on a list of all time favorites. But it had more to do with the writing than it did Affleck's performances. My problem with this choice is that Affleck is a phenomenal director. He's fantastic. Argo was the best film of last year and from what I hear, The Town and Gone Baby Gone are also very good films. I just wish that he would stick to directing. He's good in what he does, and I just don't think that being a superhero is it.
However, I'm sure that it will be a very entertaining film, as long as Affleck and Nolan keep Snyder's destruction levels in check. I don't know what they're going to do with this but I just hope that it's good. I still wish that they would have cast some one like Josh Brolin, but we're not always going to get what we want.