One quick question. When I am updating campaign bids to test how many impressions I get inside 15 minutes, in POF it says that it takes them up to 5 minutes to update it. How do you guys measure this correctly then, are you taking into account those 5 minutes, or is it more often something like 3 minutes? Or should I just ignore numbers for 5 minutes and then start counting them for another 15 minutes after those 5 update minutes pass?
I hope it is not too confusing 
From experience, if you're going to see a significant volume change you'll notice it even despite the delay in bid updating.
If you want to be really sure, lengthen your window to 20 minutes or half an hour.