Anyone had much experience of Wordpress Multi User?

I finaly want to give this a go, but the admin/ moderation side seems very lacking for the sort of locked down tightly, safe environment that i'd want it to be.

For example, when Peter Ford mentioned it at the first Edugeek Conference i thought he said you could moderate all posts and comments before the public got to see them. Looking at it now, it seems you can at best, set up an RSS feed from your student blogs to try and catch bad stuff after it has happenned.