My two get on far, far better than they ever did when they were at school. They still have the odd spat, but generally, they seem to be good friends now. My eldest has even commented that she likes her younger sister much more nowadays (though she doesn't give a reason for this!).
We had a bit of an intial blip when DD2 had been on her own at home for a year and then DD1 came out of school and joined her (DD2 was pretty annoyed!), but once we were over that, things have been great. I'm really pleased I did it for all sorts of other reasons, but this has been an unexpected bonus.
I'm glad to hear it's going well for you - long may it continue!