Product review (4 stars): Not the best for electric ovens with hidden elements....
They are easy to cut to size and very easy to clean.  My first spill was from an apple pie; think burnt caramel.  I just had to run it under the water and it slid off.  The drawback, which I didn't realize when ordering, is I cannon put the liner on the bottom of my oven because my oven is electric and the element is hidden.  I instead have to put it on the bottom rack and make sure it doesn't touch the sides or door (I mentioned it cut easily).  The pie was so juicy it ran down both sides of the pie, onto the liner and then over the edges of the liner and onto the bottom of the oven.  So I still have to clean the oven, but it did help decrease the mess, thus less to clean and smell burning.  If I could put this on the bottom of the oven; it would totally rock.