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. The search functionality tied in with Elasticsearch is excellent. One major complaint from our users is the inability to edit documents from within the repository by launching Office, something you can do with SharePoint and Alfresco. Another complaint is the UI--I personally think it's clean and reasonably intuitive, but for a user base used to SharePoint and Alfresco, it can be confusing. The other big piece of Nuxeo is Nuxeo Studio, which we use to configure our self-hosted Nuxeo instance. It's an interesting attempt at creating a web interface for configuring the application, but it's not at all intuitive and can be frustrating to use. It's also big money for the support license, which gets you Studio. Otherwise it's an IDE and XML config files if you need to make changes to the default application.
The Nuxeo documentation has come a long way over the years, but there just isn't the kind of user support here in the USA as there is for Alfresco, which means that without out support from Nuxeo, you're pretty much on your own if something breaks.
And it will break, which leads to my last complaint. It took our team a long time to get the application stable enough to use, and we had numerous bugs crop up along the way after application updates. Nuxeo was pretty responsive to fixing them, but some of them were obvious bugs that really should have been caught in testing. That said, I see improvement in this area as well, so it seems they're heading in the right direction overall.
Value for money
Ease of use