At this point I have more faith in Age of Ultron, but I'm ultimately more excited by Superman/Batman.
It all comes down to Superman being my favorite fictional character ever, with Batman also close to the top. And while I am a fan, I'm just not as big of a one when it comes to The Avengers and it's characters.
I thought Man of Steel was pretty good, while I loved the first Avengers movie. So that's why my faith for a great film is higher with Age of Ultron.
In the end I'm extremely excited by both. And I'm honestly not a big fan of VS kind of threads or topics. Posting in this one is more of an exception than not.