I purchased this item to replace the already-classic Microsoft Natural Ergonomic Keyboard 4000, which served me well for roughly ten years. I'll thus contrast it with this keyboard. The new keyboard is a fraction of a centimeter narrower and a few of centimeters deeper. It has a lot more fascinating appearance, and the materials feel better in the hand. A second stand is included in the box to lift the keyboard so that it is at the user's hands' bases. Although it is a little quieter than the 4000, I wouldn't call it silence. For me, the space bar is far more useful in this situation. So, six months after the purchase, I am still quite happy with it. There are two versions of LXM-00011 and LXN-00011 available; when I contacted Microsoft support about this matter, they claimed to be unsure of how they differ and advised asking shops instead. However, except from the price, I did not see any change.