Tire warranties are almost always for replacement with same brand and model. Any cash refund has to be considered above and beyond.
Still, I know where Cooper quality tends to run, having bought four sets as replacement for OEM, where they used to be parallel or a step up. They are not, however, a replacement for premium grade tires from Michelin, Bridgestone, or Goodyear/Dunlop or Pirelli. At least one set was not as round as it should have been, and another started separating treads at about 6 years, 80,000 miles. But the OEM Goodyears the Coopers replaced were worn out at 30,000, so it is all relative.