In my opinion, i would not bother buying this skin. Although it is perfectly good, does exactly what it says on the box, and fits the mp3 player well, it simply is not a necessity.
The clip on the back is useful when commuting on a train, but I fear loosing the Stone Plus as the clip is not very strong, and could easily fall off. Also, on the Mp3 player itself, there is a small plastic loop (like on mobile phones) on which you can attatch a neckband, and i think that this is a more secure method of holding the device.
The also skin makes the player significantly bigger. The Stone plus is absolutely tiny, yet with the skin and clin, it is no longer a shape that easily slips in to your pocket. However, this is easliy resolved, as the clip is removable (yet you can't twist it, so it's hard to put is in your jacket).
Lastly, the skin picks up a lot of dirt and dust, even fron just leaving it on a desk or in your pocket. I am forever cleaning it, and this is worsened by gloves, as is it cold in winter and the gloves make the skin dusty.
On the other hand, for the price, the skin is pretty handy, and if you have a tendancy to drop the Creatvie Zen Stone Plus, the skin is useful.