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.
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.
Smaato has a UI where you can control your line items on the traffic you want to receive. That is a key unique selling point that other SSPs don't offer. Most of the items that you will need like reporting can be done on a self serve manner and that is a big plus, specifically for changes that need to happen really fast and you don't need to deal with account managers that may take some time to answer emails.
Smaato's account management team is very professional. They are quite fast in terms of customer support, which is very helpful. One item that stands out is that they are willing to understand what you need for each campaign and what is the best way to move forward. They don't just jump quickly into trying to upsell more of Smaato's products (audiences, data) like other SSPs do.
Smaato has better anti-fraud controls than most exchanges. Even if the inventory ends up being a bit pricey, I am more comfortable running campaigns on Smaato because I know there won't be any issues with the clients claiming refunds for invalid traffic. I believe that as the industry matures, other SSPs will follow suit and prices will increase along with the board.
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.
We have seen prices a bit high, thus reducing profitability
However, the vast reach has allowed us to get more budgets and fulfill them so the net effect is positive.
We have been able to run campaigns that targeted the same user on mobile and desktop by running with Smaato and that has allowed us to get more budgets from specific clients.