they tested them on a heat source of 100W on a die surface of 128mmÂ²
here are more infos and pics about the test system:
most important they only used a slow pump and a small rad:
eheim 1046 (300L/H)
black cube radiator with 120mm papst
the results are very interesting though, the maze 4 is on rank 41!!!
would be interesting to see them test all the blocks with a much bigger rad and a much stronger pump.