I recently ordered a Jessem MastRSlide from Amazon.com through one of their retailers. When the MastRSlide arrived it had two bad bearings. I contacted Jessem by phone and e-mail and got no response at all. I contacted the vendor who promised immediate action and then did not follow through as promised. So I e-mailed Amazon.com and filed an A to Z Guarantee claim. Amazon contacted the vendor and withheld payment pending a solution to my claim. I had asked the vendor to replace just the part with the bad bearings. Suddenly the vendor got very customer friendly [I suspect because Amazon told him that they were withholding payment until I was happy]. The vendor shipped the part, I got it today and installed it. The MastRSlide works perfectly and the vendor is getting paid. All thanks to the good work of Amazon.com and their A to Z Guarantee program.