The outer shell on the one I received wasn't pulled tight, so it sort of bulges up like a badly fitted carpet, not sure if this is like it on all of these, so I have to rate it on how I find it.
The inner shell is a nice soft material and the anchor points work well with the Kindle being held snugly with no danger of it falling out if dropped. The case closure is a sturdy elasticated band, the kind you find on black notebooks and keeps the case closed securely.
The little hand strap I found to be a bit useless. It is a question of ergonomics, more so if you have a larger hand. Naturally you want to keep your hand in line with your arm which puts the kindle at an angle, so you need to put a slight turn in your wrist and shoulder. This is OK for a little while, but more than 20 mins and I found my wrist starting to get uncomfortable. I guess this won't affect everyone as factors such as reading distance, posture etc will come into play, but it is worth thinking about before purchase. If you have a smaller hand, then there will be more play in the strap and you will be able to angle the Kindle whilst maintaining posture of your arm.
I bought a real leather case for 15GBP from Tesco and it was far better.
Bottom line: A good case affording the protection you will need, but the strap may not work for everyone. At the current price of 27GBP it is not good value for money - I am sticking to the real leather case I bought from a supermarket that cost 10GBP less.