I think we can transfer the phrase from cameras here:
It (the device) can take less than you wish and more than you think.

Personally I bought a cheap, padded soft cover from eBay (€13,- incl s&h) where I put my kindle while not in use.
I do not treat it as I would nitroglycerine but I'm still "average" carefull with it. Up to now, the Kindle is still unscratched and in one piece.

I also own a fairly expensive dSLR (insured), which doubles up as a sledgehammer. (It took me abt 6 hrs to get my first scratch on the body)