These do the trick of having a few basic baking sheets around. I usually cover them with foil or parchment for easier cleanup. When grease (bacon) has gotten on them, it is very difficult to get off and has discolored the sheet itself. They also warp when in the oven over 400 degrees which has changed how flat they are. The sound of the warp (a quick pop followed by my oven rack shaking) during baking is more off putting then the angle change itself, honestly.