In IC3, Batman asks E2 Superman if E2 Dick Grayson is a “better man” than his Dick Grayson. E2 Supes says no.
What did E2 Supes mean by that? That they are equally good men, or that E2 Dick Grayson is inferior?
And why did Batman ask to begin with, is he disappointed with his Dick Grayson and was hoping for a better one?
Well, as far as Superman is concerned: 1) I interpret it to mean they’re equally good men, although 2) technically the E2 Dick Grayson is dead, since he died during Crisis, so he “isn’t” a better man, even if they manage to bring back E2. (unless of course, doing so undoes the deaths during Crisis, which I suppose it could do.)
As far as Batman is concerned I think that’s the only thing that might have made him even consider allying with Supes - 2, but more to the point I suspect it was a test of Superman, to see how honest he was, because Bats wouldn’t even believe that any Grayson could be a better man than his friend.
We discussed this in one of the recent Weekly Comic Discussion Threads, if you want some additional info.