The out-of-the-box functionality for document management is solid and their are some very nice features, like being able to view changes between versions side-by-side.
It is developer friendly and developers have lots of opportunities to deep dive into it and do their customization.
The latest version also has been released with new Web UI that needs to be explored. Nuxeo ECM is a good solution for use cases like Reuse and Repurpose of documents uploaded.
The issue was related to Nuxeo losing its connection to the database every night, due to us shutting down the database to do nightly backups.
I dislike that the pricing can be a bit high for some organizations.
And it will break, which leads to my last complaint.