This product allows us as an agency to do all of our marketing in one place which helps keep things simple for clients - they pay once every quarter so it's important that we are providing them with value at each stage! The support team is also fantastic too who can often answer queries quickly when needed (and very friendly!).
I don't think this service has any major faults or issues but if you have been looking elsewhere then perhaps give it another look? We were able to implement some great campaigns through their platform without having staff members dedicated solely to creating new content ourselves.