I bought this to replace a mouse I had recovered and that forced me to change both batteries every two weeks. And I am very happy with this choice. The mouse is rather flat, which can destabilize the beginning. Just a few uses to understand the shape fits perfectly in the hand, providing a very enjoyable. She has a small on / off button, allowing the user to save the battery when the computer is not used. It is very convenient and the autonomy of the single AA battery highs (counting several months)!
I would like to warn against by those making the CAD design on computer, this is not necessarily the most suitable mouse. In such cases, it will make more errors (validation, etc ..) involuntary several times before to take it in hand.
I advise even when not much hesitation, especially considering the price at which it is proposed!