Rubber blends of SBR and EPDM having improved dynamic ozone resistance, heat resistance, and flex fatigue resistance can be made by co-curing such rubber blends with a sulfur donor/accelerator and a peroxide curing agent. In some aspects, these blends are void of free sulfur. These cured rubber formulations can advantageously be used in a wide variety of industrial rubber products, such as in conveyor belts. The disclosure also reveals conveyor belts which have a combination of good dynamic ozone resistance, heat resistance, and flex fatigue resistance. The conveyor belt include a carry coverlayer, a pulley cover layer, and a reinforcement layer which is situated between the carry cover layer and the pulley cover layer, and the carry cover layer and/or the pulley cover layer contain curedrubber formulations according to the disclosure.