click interstitials instead of all ads lol
All ad networks are down right now I tested them all this month and Mobilecore is still the better one right now, I tested thier ads on over 10 diferent devices and I have no issues at all closing the x buttons on thier ads. Thier ads also close just fine on back button pressed so users have 2 options to close out and dismiss ads. And Yes I do think thier impressions are lower, I noticed my impressions dropped 75% switching from Heyzap but the revenue is slightly higher and i get paid weekly now instead of net45 from heyzap ads.
I just wish they also offer banner ads to go along with the stickies, now I have to use an extra ad network for banners. Also stickies they dont count impressions on those. Stickies on Splash Screens earns me extra income. 
With launch of some new apps recently im doing over $100 a week with them on google play which is good for live wallpapers.