Like others, I was loyal to the beloved Classic Whitestrips. I assumed this NEW 3D White Vivid variety would be just as, if not more, amazing 'cause I'm paying more for these.. right? FAIL! I did not see results after the full 15 days. Strips feel flimsier; gel hardly bonds to teeth for long before sliding around. The product fails to even begin to do what it claims, as it does not VISIBLY whiten teeth any better than a $3 tube of quasi-whitening toothpaste. I don't have "stubborn stains," and I'd rather brush my teeth with my foot than buy another box of this nonsense. You bet I'm mailing in my receipt and package UPC! And no worries about the one-refund limit, I won't be buying again.