I can honestly say ive noticed less lag with my efans.

 

You really make me want to do the Efans, is there a write up for it or somewhere you can't point me? Would be greatly appreciated

 

Mtz2000 did one on here that was a really good write up. I chopped and modded a 4.2 shroud and mounted dual range rover fans on a fixed temp Hayden controller. I haven't had great luck with the adjustable ones. If I had to do it over again I would just use a larger 2-speed fan and mount it directly in my stock shroud.