ok ok, lets not get off on a tangent here. Look at what people are flying its that simple. I and most others will agree that dynamax fans do not overrev OS .91's. I think all that we are looking at here is a good old, Ford vs Chevy, or Honda vs Toyota (for us import drivers) debate. Obviously both work just fine, and performance is close enough that its not really make all that big a difference which fan unit you choose. I would go with the one that is most popular in my area.