Rubicon Project is super appropriate for Publisher monetization. They excel as a supply side partner. Rubicon Project is less appropriate for Advertising buying tools. Their demand side tools have a way to go for development.
I would recommend Perfect Audience to anyone who wants to use a 3rd party to scale up. I find the audience builder pretty terrible in Google AdWords so I was looking for something a bit easier to use and this fit the bill easily.
Cleanest supply ecosystem. They are skilled at processing inventory and bids in order to streamline monetization and drive yield.
Client support is excellent. Client services is deeply invested in your business and successful at driving key business goals within your organization when working on your behalf.
The bulk uploading feature is certainly my preferred feature of Perfect Audience. This tool has made creating new ad campaigns quick and easy. I used to have to upload facebook then Instagram then another social media page and instead I upload everything all at once and it certainly makes it easier for all of us.
The support team could be a little more useful. After our implementation calls and getting everything setup, we did feel that they were not as responsive and I did find myself googling solutions to things that the support team could have helped us with.
Rubicon Project has made it easier to optimize so that we could get the fullest ROI on our inventory through their alerts on which deal needs troubleshooting.
They also send a daily report which notifies you which advertisers have low render rate which is very helpful when figuring which creatives need to troubleshooting.
The convenience of Perfect Audience has made things smoother for us. This convenience means less time spent managing ads and more time focusing on running our business.
Re-marketing features have been superior to AdWords.