I feel like it’s been pretty stable, especially now that there are more developers working on it through Mbin. I’ve been running kbin.earth for over a year and the Mbin developers have been very helpful in resolving any issues I (and other admins) have come across.

Honestly, the worst thing that’s happened to Mbin was the kbin.run instance suddenly shuting down and the admin/developer disappearing out of nowhere, but that could easily happen to any Fediverse instance (Mbin, Lemmy, Mastodon, the software doesn’t matter). And, that was way better than what happened to kbin and kbin.social, where the admin and solo developer went silent, causing kbin itself to dwindle out.

All that to say, Mbin learned from Kbin’s failures and focused on having a group of developers instead of just one main developer (which caused a single point of failure). So, yes, I would indeed consider Mbin stable; just pick a server you believe would stick around for a while, and hopefully, if a server does ever need to shut down, they would at least give a warning in advance (I know I would).