Glass is an insulator. That means it takes longer to heat up. But once it does, it helps to maintain a stable temperature (even in an oven turns on and off intermittently). To compensate for the additional time it takes to heat up, you might need to extend cooking times for 5 or 10 minutes, when baking in glass.
Glass baking pans are best for cakes, which bake for a relatively long time at lower temperatures. Also keep in mind that glass can shatter if the temperature changes too quickly (like when you transfer from the oven to the counter). So be careful!
Metal pans heat up and cool down quickly. That means they are great for items baked at a high temperature for a short time. The type of metal you use can also make a difference. Metal with a dull finish absorbs heat faster than shiny metal, so that cookies baked on a dull cookie sheet might get too dark on the bottom before they are cooked on top.
At Wellness Bakeries we recommend that you use safe, nonstick metal pans like those made from stainless steel, stoneware or cast iron – NOT traditional non-stick pans that contain perflourates (PFOA) which are known endocrine disruptors.