A recent past Round Robin Test performed on a 400 kV insulator set showed a large spread in findings among the four participating laboratories, with maximum relative differences observed in tests under wet conditions. In the light of this, it was decided to perform a new set of tests, this time on a smaller set-up such as a short cap & pin string. This would make it easier to evaluate the influence of individual test parameters on flashover voltage. This presentation reviews findings from further testing involving a smaller insulator configuration under rainy conditions and where more parameters have been varied.