Sorry that you had a bad experience using GitLab.com. We’re working on improving stability and performance on GitLab.com. There's several ongoing efforts in improving stability and performance (Gitaly[1], Infrastructure issues[2], ...)
We always run the latest version of GitLab on GitLab.com and we’re working on making (almost) all our deploys downtime free (Issue: [3], MR: [4]).
Of course, you can opt to self-host GitLab. It’s easy and quick to setup and requires very little maintenance via our omnibus package [5], and of course, we're here to help you if you get stuck along the way.