I bought this BOSCH Dishwasher because I was sick and tired of replacing the upper rack roller assemblies on our old dishwasher.  This dishwasher has BALL BEARINGS on the roller assemblies!  VERY well designed and built!  SUPER QUIET - 39dBA!  You literally cannot hear it when running - you have to rely on the little red light glowing on the floor to know if its running or not.  And it's FANTASTIC at getting EVERYTHING clean!