When I bought my Blackberry 8520 I wanted to keep it in top condition, as we all do when we get a new gadget. I have always preferred cases that wrap around the mobile phone and that allow me to use the phone without having to take the phone out of a case. I write and read a lot of texts, so I usually opt for a cover as opposed to a case. When I bought my Blackberry I tried various types of rubber skins and clip-on covers, but when I heard friends talking about the leahter cases made by RIM they began to appeal more to me.
The major selling point for me is that the case has a 'Magnetic Proximity Sensor' within the case which determines whether your Blackberry is in the case or not, and shuts off th screen if it is in the case to save battery life. I use my mobile phone more and more these days, and although I have a spare battery it is useful to prolong the life of the charge. You can also use options within the phone to select different notification settings for incoming calls and texts etc.
The case itself is very stylish, a smart leather holster with the Blackberry logo on the front right corner of the flap. It is a shame I can't check for messages etc. whilst the phone is in the case, but this isn't much of an issue now as I have got used to it. Saving battery power can be a problem when spending long periods of time on the phone, and I can now go away for a full weekend with just a spare battery and this case and I have enough battery life to last me.
The stitching on the leather is secure and holding up well and because it is made by RIM (the makers of Blackberry) I know I am dealing with a product from a trusted brand. For about £10-£12 from Amazon an official RIM leather case is now a must for heavy phone BB'ers!