How heat resistant do oven mitts need to be?

For standard home baking (325 425°F), any quality oven mitt rated to 450°F+ is sufficient. You're not holding items at oven temperature for more than a few seconds. For grilling, broiling, and deep frying, look for 500°F+ ratings. The 932°F gloves exist for brief contact with very hot surfaces like pizza stones and grill grates, not for sustained holding.