We self host gitlab, so its very stable. But Gitlab also kind of is enterprise software. It hits every feature checkbox, but they aren't well integrated, and they are kind of half way done. I don't think its as smooth of an experience as Github personally, or as feature rich. But Gitlab can self host your project repos, cicd, issues, wikis, etc. and it does it at least okay.

I would argue GitLab CI/CD is miles ahead of the dumpster fire that is GitHub Actions. Also the homepage is actually useful, unlike GitHub's.