I ordered 6 packages by mail. Opened two (4 blades) and none of them cut evenly. My mat works fine with other blades. At least two of the 4 were not exactly round and had some straight places and I did have to clean the sticky residue off with alcohol. Maybe quilters ordered so many that the manufacturer hurried the process to replace stock. They did give a refund. I then tried the store in another town and they did not have them in the stock.