9front is probably the most niche operating system you can think of. There's a community on it called cat-v and the operating system itself is as terrible as the people.
There are none.
It does have an installer. It's just a stupid script but at least it does have something.
Hardware support is... let's say if you have anything newer than a Core 2 Duo, it's not supported.
What are you gonna use it for? It has no software
I think there's one server somewhere that uses it. 9front is really just a research OS without any purpose other than reading it's horrid source code. Other than that, the developers use Windows or OpenBSD.
+ is a pro, ? is a mixed opinion, - is a con
+ You can learn a thing
- It's so useless I can't even consider it a fucking OS at this point
- Shit community
Jackass-tier challenge: use this as your main for a week.