I've heard a ton of stories about .io, IMO, they play fast and loose in a space where that isn't okay, and they get away with it mostly because they are a ccTLD.
The last time someone I knew had an issue, they had to get a senator to make waves to get anything resolved.
I regret going with .io for my personal domain name. At the time I thought it was cool, but they've since raised prices and hearing things like this doesn't instill confidence...