There's not much to say about this item - it fits snugly and looks fine. The volume and on/off buttons are covered by the case - while this doubtless adds protection, it can make locating and pressing the switches a bit of a pain.
The clear plastic back is okay, but it's more scratch-prone than the rubberised case and is already slightly scuffed.
For five quid though, it's bloody good. I was looking for the official Nexus bumper but it was out of stock and I needed something to put on my phone as soon as it arrived, so I went for this. I'll probably upgrade to the official bumper case at some point when I get fed up with trying to find the buttons, but for now I'm more than happy.
UPDATE: After a few weeks, all of what I says above still stands. However, one problem with the transparent back is that when grit and dust worm their way inside, it's visible and looks horrible. You need to take the phone out of its case every week or so to clean it and prevent scratches.
Still (just about) four stars, but only because of the price. I'll be buying an official bumper case now.
