I recently stumbled upon
this review at systemcooling and found it to be very thorough and done on a decent testing bench too.
I have previously read reviews at systemcooling but they were mostly show-and-tell, this though includes c/w vs. flow, pressure-drop vs flow, c/w vs pressure drop et al.
Check it out:
http://www.systemcooling.com/mcs_wc-01.html