Just had the whole case replaced under warranty with cracks developing by the palm rests & also on lid by Apple logo. The dealer informed me that the issue of the cracks developing by the palm rests had not been rectified & could happen again. Of course, if it happened outside the warranty I would be out in the cold, so I have attached self-adhesive silicone bumpers at each end of the screen. They are marginally thicker than the protrusions which contribute to the cracking & work really well in cushioning the lid on closing.