Originally Posted by will76

for a limited test, over short period of time... it should be PPS.

If Site C gets lucky and gets a whale who spends 20K (likely would have spent 20K on any of the top 5 cam sites since they all would have quality girls and decent system) then it would look like one site was 1000x times better than the rest, when it was just pure luck of the draw. You can't skew the stats with PPS.