lucy24 - 2:49 am on Mar 25, 2013 (gmt 0)
If the links are completely loathsome you might even be better off with a 404 because then it just makes the linker look bad :) There are also the human visitors to consider: are the repeaters-- bookmarks and so on-- worth keeping? Humans don't know from URLs. They just know "This good stuff used to be here and now I get a page saying it's been removed." Hit a 404 and you might think there's a mistake in your bookmark, so stick around and search the site.
Google stops crawling 410s pretty soon, but Bing really doesn't seem to make a distinction. I've got whole directories where the only 410s are from the bingbot.