CPX scammed me. Closed my account without even a email, no idea why, had been running with them over a year. F them.
i been with cpx interactive for over 3 years and they never missed a cent. they always paid all to me. also i think its the best ads program among these that accepts some sites that some other ads programs might not accept (like mine). but i know they also dont accept every one. i think your site needs to have a certain minimum traffic. though if you just use their ads plain on your site, my personal experience in 3 years on my sites and many other friends sites is that some of their ads redirect ppl to other sites once in a while, (chinaontv.. jookeroo..) its very annoying. but if you ask them to disable 3rd party ads on your account then you dont have this problem anymore. maybe if they havent paid you, double check that your paypal address is correct?
CPX or cpxi or brealtime is a scam. Appnexus closed their application. Look around how many publishers on digitalpoint weren't paid for months.