Here is our list based on over a year running 1,000,000s of impressions (not on this site, but we wish 
These are our thoughts based on networks we are part of. If you wondering about one we do not mention, we have not joined them yet.
1. Adsdaq - Been running for several months, filled 50% during holiday season , High CPM, Pick your CPM Rate, Run It first, then Right Media Second, works great! Good reporting, easy to use interface.
Adsdaq
2. Right Media - Direct Media Exchange - Been running for 6 months, Pretty High CPM, Good thing is you can set the CPM you get on other networks and they only fill if they beat the CPM you set. Great because they have many companies in there exchange network including (Xtend, Vizi Direct, Rydium, Revenue Science, Oridian, Directa Networks, Bannerconnect Networks, Active Response Group, Adtegrity, CPX Interactive, and Remix Media). They also have great reporting, and you can use them as a free ad server for any direct sales etc.
Direct Media Exchange
3. Tribal Fusion - Been running almost a year, high CPMs but hard to get into, Great pop-under CPMs, Ok Reporting
Tribal
4. Burst Media - Decent CPMs, Sometimes get direct advertisers, Good Reporting
Burst
5. Casale Media - Good Popunder rates, seems great for few months then CPMs went down. Don’t know if it was seasonal or what, but since they are later fill in our system probably is part of the reason.
6. Value Click Media - Decent Popunder rates, lot of fill, don’t like there reporting and slow interface.
7. Realtech Network - LOW Cpms, bad interface, ok for final fill
Realtech
8. Robert Sherman - Terrible Reporting, LOW CPMs, ok for fill, one good thing they prepay in $25 increments, although you never no how much you going to make because the reporting is so bad.
Robert Sherman
Oops only 8, well Again this is based on our own experience with ad networks we have used. We’ll try to get more detailed but wanted to get discussion going with others…
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