The traffic is super cheap, once you get it up and running. You can just set a bid and you're good to go.
Super hard to get approvals, even on a clean, compliant lander. Support is slow to respond as well.
I believe this tool offers good scale of distribution as it has some large publishing partners within it's network (such as Huffington Post and BusinessInsider). It's been easy to get the content ads up and running and the reports that you get are easy to digest. The interface is well designed and doesn't require much training to use.
Spam. Along with the good placements there is also a lot of spammy placements, which drives spam referral traffic and can sway your campaign data. However it is possible to filter these out from the report.
It's easy to get your new campaign up and running and approved with Taboola. The interface is pretty slick.