The Fellowes Silicone Wrist Rocker looks like it would be an evolution of the gel padded mouse mats, allowing for much more movement of the wrist, but unfortunately is sadly cheap and uncomfortable. The concept is a great idea, but the gel padded mouse mats are comfortable and allow the wrist to rest properly on it at a comfortable height and at a variety of angles; this doesn't. The way it moves means you have to position it at exactly the right angle for it to feel even slightly comfortable; however, even then it is quite tall in comparison.
The construction of the mouse mat is cheap, flimsy, 1mm thin silicone, which when you move your mouse on makes an awful noise.
The only saving grace - and this is subjective - is the colour. I adore the orange, it's gorgeous and I was truly looking forward to using it but sadly I just can't. Such a shame!