I installed 2.9 shortly after it was released, I always test versions before deploying to the people who need to rely on it. I struggled with various flaky server issues like publishing, first figured that I was doing something wrong, Then finally found out I could not test branch versioning with 10.8 on the server because it's simply not compatible with Enterprise less than 10.9. I dropped back to Pro 2.8 and things have been working better for me.
I wish they would just say in the system requirements that it wants to have a 10.9 server. Maybe it's supposed to work with everything BUT branch versioning? But that was my experience. I am not going to go back up to 2.9 until I have deployed 10.9 on my server.
My team statewide has settled on 2.8 and that's not compatible with 10.9. I can't have two servers because $$$. It's awkward.
