The ability to easily deploy multiple ad networks at once, without having to have separate accounts for each network. It's also nice that I can manage everything from one interface instead of logging in with five different interfaces! Not much so far since it is fairly new but seems like they are still trying to figure out how things work best. Have had no issues thus far. We were using several 3rd party ad servers before switching over to polymorph. This was definitely better as we weren't tied down by any particular partner or vendor - we could pick which ones fit our needs most.