Been using the sitescout adserver for some buys and it has some pretty bad ass features, one of which is "impression recycling" , basically for those who may not know is that you serve a creative then you set a recycle group and have other ads in there and after a set amount of time it refreshes to the recycle group basically you are rotating creatives to the user but your only pay for that impression 1 time. Now my purpose of this thread was to see if somebody else can chime in on what kind of refresh rate times they have found luck with and if there are some tips or tricks involved in this to squeeze the most out of every single impresssion.
on a side note if anybody is in the market for a new adserver, sitescout adserver is something i would highly recommend, rates start at .08 cpm