adversal pay much more if you have much US traffic, and also they pay via paypal. otherwise you can choose adbrite.
I would personally go with Adbrite rather than adversal. But, there are other networks that pay higher and faster. The only problem with adbrite is their payments. It's NET 60.
AdBrite. I love it. Used alongside AdSense it can increase your earnings by around half. Not bad for no extra effort.
Adbrite is a much better option, I think. I've had lots of success in it. The approval in Adversal takes forever.