Here lives a very tired cat indeed!
My cat absolutely loves this - so much so that just the sound of the mouse's keychain jangling gets him rushing up to me from anywhere in the house. He's an outdoor cat and very energetic, so this is ideal for burning off excess energy when the weather's bad - he'll thunder about chasing the infamous red dot for ages.
The mouse itself seems to be good quality, and the laser is bright. The rounded on/off button isn't the most comfortable, and has to be held down to work, but I've no problem with this type of switching as it means it won't be left on accidentally. It's a shame that the mouse has to use three LR44 coin cells (not a fan of these), but they're doubtless needed to give the necessary power, and at least a set is supplied with the mouse.