RevenueDirect is a 7.5 out of 10.
It is best for low paying keyword domains, such as youtube typos, myspace typos, etc. The CTR is very very good. They pay for multiple clicks (unlike Sedo).
For one of my very high traffic domains, CTR was 13% on Sedopro, and that was the max I could've gotten it there. On RevenueDirect, it went upto 38%. Although, on the downside, RevenueDirect payed less per click and didn't count all the traffic. For instance, one of my domains on Sedopro received 11,000 unique visitors per day avg. On RevenueDirect, it only counted 8,000 uniques.
Overall, for low paying keywords, RevenueDirect did slightly better in RPM than Sedopro. (Note I have a 30% bonus on Sedopro).
In all honesty, since most people don't have 30% bonus level with Sedopro, you will probably do better with RevenueDirect. Also, some domains that are blocked on Sedo/Sedopro are allowed to be used with RevenueDirect. Sedo claims that Google doesn't allow them since they use Google's feed. Outright lie. RevenueDirect also uses Google feeds and you can add them in without a problem.
PS
CTR starts out low on RevenueDirect then it builds up as the optimizer goes into affect. Takes a full week to see full potential for the CTR.