From what I know, 0.00003 BTC/1000 impressions are not the highest stable rate in market for overall traffic. I am getting 0.00006 on average from Popads. The only thing I like bitcoadz because their pop can choose new tab pop which doesn't annoy your visitor so much.
In start they give good earnings I think you are new on pop ads after some days you will get lower than $0.3.
I personally used pops ads more than a year just for $0.25 average earnings.you are saying $0.6 stable earning its joke.