Here are my recommendations
Exoclick - i bought from them awhile back and I need to do it again. Now that they have wizzo on board i know i will get the best support possible.
TrafficFroce - lately this has been my 'go-to' to test any thing im working on. Great rates and now they got popunders 2.50/cpm that i am testing right now if ross would kindly login and approve my ad (
[email protected]) heh
TrafficShop - I really like their bidding system to get you higher up in the que if you know something is really hot and you want to spend a little more to get it rolling. I tried to use them to test some tracking stuff and the traffic came so fast that my firewall filtered most of it lol
Chris