Any experience you can share? Are any of the sites listed worth the money for SaaS companies like ours?
Hi Sebastian, I tried it multiple times with different budgets and different inventory (mostly dev audiences so tuts+, stackoverflow, cssguide, scotchio, etc). This wasn't for a side/indie project but for a growing startup (Pusher.com) with a larger budget (50K+ / month)
If you are looking for direct conversions, this is not going to work. However, for branding, it was pretty good, people saying "I saw you on Scotch.io|Stackoverflow|etc"
Also, what we found out is that if you look at it from a multi-touch attribution model, a view or click from these campaigns did contribute to some conversions but nowhere near the quality of content/SEO or google ads (capturing intent) for us.
Finally, they have some good ads stuff with Pocketapp or sponsoring content on Firefox start page. If you have a piece of content that you know convert well, I would recommend giving this a go since it is pretty novel (no ad fatigue) and barely used (relatively cheap). Bear in mind that this option is only for the US market.
Hope this is helpful.