HARO outreach isn't a fit for every client, and you probably won't get a lot of links for any given client (more like a trickle). But it does work if you practice the suggestions in that post long-term (as in you shouldn't try it for a month, not see results, and conclude it doesn't work). Good back-burner activity.
The most important tip on that list: "1. Reply within the first 10 minutes of getting the HARO email. When I started sending in pitches fast, my success rate improved significantly." And I would change it to 5 minutes.
New advertising option:
A review of your product or service posted by a Sterling Sky employee. This will also be shared on the Sterling Sky & LSF Twitter accounts, our Facebook group, LinkedIn, and both newsletters.