Well, Polygraphite advertizes that their stuff is quiet unlike Energy's. Their bushings are graphite impregnated (graphite is an excellent lubricant). This would lead me to believe that theirs would be the least likely to squeak. One huge plus to PST is you can get an entire suspension rebuild kit from them real cheap. Doing rubber through Moog is quite pricey if you also intend to replace tie rod ends and ball joints.