Interesting review! Nice graph and it is well done. I would like to see how the heatsink sits on the cpu. Can the heatsink be rotated 90 degrees on the motherboard? Will it interfere with the northbridge heatsink?
Can the pushpin connectors be substituted with the Thermalright 775 backplate with the metal screws? I wonder if this would improve the cooling!
As far as Xigamatek goes there is no current mounting system that would allow you to use screws and a metal back plate, their focus here is to keep the cost of their coolers down by not using expensive mounting brackets with spring loaded screws and metal back plates. Take a look on ThermalRight USA website under accessories and you will see how much these units can increase the total cost of a cooler if included as parts for the mounting and that might give you a better idea why Thermalright's coolers are more expensive intially.