My wife and I went to a local vacuum store to test drive Simplicity Symmetry Premium. They also had a Synchrony Deluxe on display. As part of the test, a cup or two of sand was dumped on a rug. After a pass or two with the Symmetry, they did a few more with the Synchrony to show how much more it would pick up. Then both my wife and I made several more passes over the same area with the Synchrony. I was quite surprised that even after what was likely 15-20 passes, there was still considerable sand evident in the rug. With each pass we could see a lot of sand suspended just ahead of the vac. Would have thought a brand new higher end vac would be more efficient than that. Is that unreasonable or is it more likely that that specific unit was a dud?