I liked how easy it was to create campaigns, track them in real-time for ad optimization purposes - this made setting up all of our lead generation efforts so much easier! The email templates were also very helpful because they allowed us to send automated emails straight from an inbox instead than having someone log into ooze every time we wanted test out new campaign messages or images/videos.
It would be great if there could have been some way added where you can easily attach your Facebook page link within each individual template file as well (as opposed to creating separate files). We love using Oozel's service since their team really does know what its doing when building successful ads & tracking stats are kept right next door at hand which makes things run smoothly with no issues here along my end :).