The normal version works fine- no complaints. However, in mobile version it displays giant ugly YOUR AD HERE! boxes all over the page. Why would any website owner want a user to see that? Why not just leave a blank box? Obviously we can tell when there's no ad on a page. We don't need to air dirty laundry.
After I installed this, it took me weeks to notice that my mobile site bounce rate had gone to 100% and no mobile users were staying on my page more than 5 seconds. This plugin literally killed my mobile version.