I haven't had much trouble with it. I just moderate the first post by a user and let the rest through. This has prevented any spam from getting through to my 1200+ member group.
Same here. Perhaps I'm not moderating large enough groups for this to be an issue, but it's never been a hassle.
What I really like is that I get mail telling me there's a moderated post, and I can approve simply by replaying to the meta-message.
Now, it is annoying that every so often users with approved posts are not correctly then set as auto-approve, so there's some occasional intervention needed, but Google groups has worked quite well for the 4 or so groups I look after.
