I wrote about it in my blog post "Goodbye GitLab; Hello Gitea, Nexus and Drone": https://blog.kronis.dev/articles/goodbye-gitlab-hello-gitea-...
That said, I still find the UI of GitHub and GitLab to be a bit better than Gitea's (the whole organizations/groups navigation feels better), though Gitea is immeasurably more performant when compared to GitLab, especially when the available hardware resources are limited - in the case of 4 GB of RAM being all that I could afford, it's the difference between a really snappy and annoyingly laggy UI.
Admittedly, now it's Nexus that loves eating my resources, though for the most part having software like it for managing most of my container images and other packages is pretty cool and worthwhile, though one might also want to explore the alternatives, such as Artifactory or something else.
Also, personally I find Drone to be a bit less capable than GitLab CI and its documentation isn't quite as good in comparison - though that's a given, since it's an external tool developed by another company. Though I guess even Jenkins would also be a viable alternative (despite it having certain issues with plugin stability etc.), or many other CI tools, given that Gitea is actually decently supported!
In summary, even if there still are a few challenges here and there, the whole setup is a lovely way to self-host your own projects and everything around them in a cost effective manner and whilst also staying in control over your own data. Gitea is an important part of this and overall I'm really glad that we have cool software like it nowadays!
At the same time, I'm more than happy to use GitLab or something like it at work, as long as keeping it working nicely, up to date (and paying for the servers) is someone else's responsibility.