Some people online say you can buy Duralast pads from AutoZone with a lifetime warranty and return them after they are worn down for a new replacement set free. Others say the warranty only covers defects. I bought Duralast for one of my cars a few years ago and will probably try it when I need new ones, but I think it's YMMV.
Pads and rotors are something I'm willing to pay a little more for to buy locally, for easier returns just in case. They are high volume items for local auto parts outlets, due to standard sizes and fitments, and they are often on sale, so I usually go with a higher quality option (gold, platinum) store brand.