The MultiSort component was "fixed" in late 2009 to identify optimised fields and ignore the rest. That means it provides sorting on 5 fields only - date, title, ID, security and type. Considering there are typically just a few security groups and content types it's hardly worth using. Installing URM gives one more field. Whoopdie doo.
I'm sticking with
Database.Fulltextsearch. Sure it's slower to rebuild and doesn't have fancy drilldown features - but it works the way it is supposed to.