[DanielCoffey]

While it doesn't zip closed like some of the armoured cases, the Oberon cover is fairly rigid and also slightly larger than the Sony reader. If you watch the sample video on the Oberon site about their Kindle reader, you will see that this is to help protect the vulnerable corners. The screen is protected by the fact that the sides of the cover are two thicknesses of leather plus a felt pad plus a rigid plastic insert.

If you routinely drop your Sony Reader on the floor, you would be better off with a rigid neoprene zipcase with impact foam inside. Leather covers (also including the M-Edge) are a compromise of style and ease of holding on the one hand and protection on the other.

EDIT : remember to treat your reader with the care due to the fact it has a thin screen of glass and you should be OK. The reader itself is not designed to be dropped at all. The majority of covers available at the moment are designed to offer excellent protection for a reader put in a bag or rucksack and "we will help if we can" protection for a reader falling from a desk onto a hard floor.