BillA, Rosco put on cooling-masters a link where ou can find a PQ curves from Laing with a ma flow rate of 570 lph instead of the 350 lph you and Rosco measured.
His body is also different (fixations) so we believed there is a new version of the pump. In fact the old PQ curve is extrapoled over 270 lph, and new PQ curve is a full measured results from Laing.
Rosco is waiting for some answer because you and him have same results and it correspond to the old PQ curve
EDIT : the link
http://www.laing.de/10Produkte/40Pum.../GleichDDC.pdf