whats better??? SLP loud mouth or Magnaflow or magnapack cat back? whts better SLP o/r X or magnaflow o/r X?? im going to be getting a o.r X pipe and maybe cat back and cant decide. what are your guy's opions on the SLP loudmouth? Magnaflow catback? magnapack? which sounds the best? can somebody help me is there any difference between the magnaflow X and the slp X if not then i dont really care ill buy which ever X my cat back is. so SLP or some kinda of magnaflow???