Maybe DEX Network is good in video ads, and the eCPM as high as over $1, if you have interesting in it, pls visit it: http://www.cpmadsnetwork.com/
I've been using AdStract.com for the past month to monetise my videos. They seem pretty good and you earn well, when the videos actually appear (as long as people watch them) You can use their tags to get the video ad to overlay your video. There is a thread about them here in this forum. Opinion is mixed, but in the month I've been working with them I've found them very straight forward and transparent. And like I say, when the videos appear and people watch them the CPV rate seems very good.