To be fair, it has long way to go to reach the tooling, testing and maturity the JVM has in linux.
This is kinda what I was alluding to. I don't think it's quite ready for primetime. That said, I wouldn't be against seeing it in, say, Fedora's bleeding edge repos.
Is Mono ready for the prime time? Because it's most certainly already in Debian. It's just that MS doesn't give a shit about adoption on the "cancer" platform. They'd much rather we all wore the Windows ball and chain.
So you're one of _those_. Noted.
PPA is specifically designed for packages that are potentially not stable. And you can find dozens of garbage packages in Debian repo without even trying all that hard.