No real advantage other than it being a community based project that you may, or may not want to support. It's there for those who want to use it.
As others have said, vpsboard's hsoting IS gitlab, in terms of the software. I don't know much about Bitbucket but I thought they mostly ran Mercurial. Github creeps me out. They are like Facebook for programmers, full of obnoxious user tracking, and a real-name-required, one-account-per-person registration policy. Companies can pay github to host private repos, but only personal accounts can check in code. I.e. the company you work for (if they host with Github) doesn't give you a github account the way they typically give you a gmail account. They instead add your personal account to a whitelist, so you can access the company repo. So Github knows the real name of everyone who can access the repos of any company they host, and they know the names of the companies and projects whose repos you can personally access. That basically means they track your employment or client list as you work with different companies over time, very valuable info that they are sure to try to monetize sooner or later. Do you think they will always keep that info private? How many times has Facebook or Google adversely changed their privacy policies (answer: plenty). Even if they try to keep the info private, their site uses Ruby on Rails (i.e. exploitville), so good luck with that. And with any company holding a lot of sensitive personal information, an eventual turn towards evil is generally a safe thing to bet on.
The evil is that you may not have a choice about using it for business matters. If you work for a company and the company uses github, you have to use their github repo in order to do your job. And because you aren't allowed to use separate accounts for separate companies/clients, Github can track and monitor your business relationships.Github transformed into a coder Facebook because they need money. I host opensource on github but don't use it for private or business matters. If this community is creating a opensource project it should be hosted on a public repository to attract other programmers.