I used to be BIG into rx-7's and knew Aaron (the guy who wrote the article) through the rx7club.com...he is a very smart man. He knows the Wankel rotary engine inside and out, but I disagreed with him on this. I had a turbo RX-7 in Houston that continually ran hotter than it should, I went back and forth trying to decide on what to do. Aaron (and others) said that I would be worse off going with an efan...to make a long story short, I was on a road trip and the fan clutch went out and I was in a bind, there were no 7's in the local junk yards where I was stranded so I went to Pep Boys and bought a Black Maxx efan and installed it to get me home. I never had another temp issue after that, so I left the efan on! It was a great fan, I got the big one (300cfm's I think).
Point being, I definitely gained better cooling by doing an efan.