Also running into an issue now with Interstitial ads. Ive noticed a big slow down when using Runtime enter frame events after an Interstitial has been created. It runs well if I dont create the ad but like a dog if I do. It seems that although the ad is dismissed, it is doing something still. I need to be able to remove it.
So, this is the code to create the ad:
interstitialAd = new InterstitialAd(adUnitID);
            AdRequest adRequest = new AdRequest();
            // Enable test ads.
            // adRequest.ForceTesting = true;
            interstitialAd.ReceivedAd += OnAdReceived;
            interstitialAd.LoadAd(adRequest);
            interstitialAd.FailedToReceiveAd += OnFailedToReceiveAd;
            interstitialAd.DismissingOverlay += OnDismissingOverlay;
Now what can I do to remove all that completely? Is there some kind of removeSelf for c#? Do i remove the instance I created :interstitialAd
and then
AdRequest 
OnDismissingOverlay is an empty void which just lets me know it has been dismissed so I just need to place whatever code in there.
?