I've had a few Kindles and have always bought the official cover, despite the fact that cheaper alternatives are always available, mainly because Amazon have unerringly supplied me with quality products and the official covers have usually had some form of extra functionality.
In previous covers this has been provided by the built-in lights in the cover, but this time, as the Paperwhite has its own light, the cover automatically sleeps and wakes the Kindle as you close and open the case. And I have to admit that, while it's not exactly difficult or time-consuming simply pressing the button on the Kindle, it's a little touch that adds just a little bit more joy to using the Kindle.
The cover itself is very slim, fits the Kindle perfectly and looks neat and smart sat on your desk or bedside table. The front is ever so slightly padded and the brushed metal accent of the magnetic clasp adds to the appeal and seems to keep the cover reasonably securely closed, as long as you don't wave your Kindle in the air. The texture of the leather reminds me somewhat of some old leathery library books that sat on the shelves at my school and evokes feelings of quality and learnedness.
At the end of the day it's a cover, so there's nothing to lose any sleep over, but what it does it does well and it's certainly a quality product.
Marked down by one star as it's probably a tenner too expensive.