Zoom Street/Strip Kevlar Clutch & Pressure Plate (Small Block)

i personally used to run a hayes set-up...was stiff on the leg though..b/b design...I hear nothing but BAD things about them as of late??..I have a friend who recently changed to the centerforce dual friction unit and says pedal feel is good...he still uses the clutch overcenter spring but I have heard that it should be removed for some reason...can anyone add to this??? do you run the spring??? not run the spring???