Rotation does not seem to change results much - Giglamesh has tested 5 blocks independently and rotated each one and the only one that showed a real improvement was the Koolance block.
Images are starting to add up I have about 14 so far and contact for the wb's generally is poor. I will post a catalogue of results so far later this weekend.
Keep in mind that the sink is only half the equation, the IHS comprises the other 50%.
The sink could be tested separately using a flat plate or a glass slide with the C/P paper and a clamp like this
which will apply approx 45-50 PSI.
The test would tell you whether it is the sink or IHS is not flat
Clean Print BTW