I'm on 3 networks that use +q for owner Jethro_. isowner does not work on any of them.
IMO, This operator doesn't work consistently across enough networks to be used in posts here. It's much smarter to just use .pnick and the symbols listed here -->> //echo -a $prefix <<-- ,as isprotect doesn't work on a high enough percentage of networks either.
I'm not just blowing smoke ;/ I did an audit of over a hundred irc networks about a year ago to determine what method would be best to use on my posts.