Well, had to give this a one star.  I have attached photos of the problem.  The bearing on one side of one of the wheels is missing which would make the door wobble back and forth, and unusable for my install as the door would hit the trim when sliding.  Other than that, the materials seem to be of good quality.  I suppose if I were sent a replacement part it would be okay, but it also holds of my install until I can get the new part.