See also: How to deal with persistent Spam-Users?
I know of a similar question here, but it does not really answer my question:
How do I deal with users which have just one purpose: Spam?
On Super User, there are 1-rep users which are just posting links to commercial products, and most of the time it's about data- and password-recovery tools. They're human spammers, though, and the answers are always different but always contain the same link. By now I always flag one answer as "Needs moderator attention" and add "spam user" as a comment. Is this sufficient or wrong?