If anyone hasn't changed to all mooncloth, you need to do it now. It is absolutely ground breaking esp as a Spriest. As a Shadow Priest. I have PW:Shield on 15 sec cd which suppresses all movement impairing effects and Fade on 15 sec cd which removes all moving effects. Fun Stuff!!!
I just think that the 4 sec immunity added to PW:Shield is just too class defining and should be made to all priests and not just ones with 4pc bonus. It totally changes the things and the way you play a class more then any other 4pc bonus.
My suggestion is to innately put the 4 sec immunity onto PW:Shield itself or perhaps add it to fade as a basic ability. Then all priests can see the greatness of what is Holy Walk.