We are 7+ years into one. Each is different, but we have a pretty laid back, hands off birth family. I can do my best to give any feedback, I know some people who have had to set boundaries.
We are here with both set of BPs. We reach out more than they do, and we each hold up our ends of the post-adopt agreement. With DS (so like 6.5 years ago), we had some social media concerns about BM posting his pic, but we were basically told that there wasn't much that could be done. It hasn't been an issue in forever.
I am happy to answer any questions either here or via PM.