I did some short testing in the same out side temps same driving condictions and routes with my brand new oem fan vs my Taurus fan. The Taurus fan did about 3 -5 degrees cooler than oem and a lot cooler at idel. This was tested over a couple of days of testing with both. Via digital water gauge.
The problem with the 300zx and electric fans is that people would use shitty fans or not set them up right and they got a bad rep. They taurus fan moves about 4000cfms and is with in two inches of the radiator.