After buying a Lachesis about 6 months ago, and being rather impressed with it, I thought it would be a good idea to protect its feet and enhance the experience further with a Razer mouse mat. So after reading about this 'desktop skin' on Razer's website, it seemed too good to be true.
I ordered a Sphex as soon as it was available, so I've had this about a month now and yes it is awesome. I won't try and explain what the surface feels like, because there's no point, let's just say it's the best surface you will ever put your mouse on, and moving the mouse is an absolute joy.
It is as thin as they say: 2 sheets of standard paper. The only thing that doesn't quite live up to the hype is the 'infinite' adhesive bottom. There is a lattice of adhesive on bottom of the mat, which to the touch hardly feels sticky at all, but although isn't sticky like tape, it obviously uses the same principles as tape. (it isn't some magical material).
Sure it's impressive, but on the near edge of the mat where it gets more pressure and rubbing from your hand, a tiny bit of the sticky stuff has started to come off on to the desk (nothing a bit of lighter fluid wont sort out I'm sure). But seeing as once the mat is on the desk, it's there for good, it's not really much of a problem.
That's only a minor gripe, but overall it performs and looks great. I know it's marketed as a gaming mouse mat, but it's obviously awesome for design work too or anything else for that matter - would recommend to anyone.