I bought the Airraid one a few years ago now.  Did it make a difference.  a little,  Would I do it again, I am not sure.  I noticed much more of a difference with the electric fan and header additions.  Every little bit helps on these rigs.  I know a lot of the Charger/LX guys hate them and say they are worthless.  I do not have one on my charger, but that is also a totaly different machine.