Their support was excellent. They allowed me to build my own extensions, which are not available in their base package out of box (such as custom reporting). I also liked that they offered multiple payment options when purchasing ads from them, including using credit card processing or Paypal payments directly. The interface looks nice, it's simple - no frills needed there! It would be helpful if i could access more metrics via API/REST endpoint (like other ad servers do) like impressions share