I just bought a bunch of upgrades and I thought I might risk spending a tenner on a proper mat. My last one was really good but it was starting to wear down after a few years of use, so I wanted a new one that was going to be good too. I read reviews of this thing and thought I'd give it a shot. I'm really surprised by it! It's great. It's as flat as a piece of paper, and it somehow sticks to the desk as though they used glue, but you can peel it off and restick it over and over because it's not actually glue. It's also pretty big so you can whip your mouse around in gaming and it wont ever go off the sides. And lastly, the surface is perfect. It's smooth so that the mouse moves really smoothly and easily, but it also allows the laser to be extremely accurate. I play a lot of Arma2 so it's really been a surprisingly nice little upgrade for playing games like that.
I've got the Sphex too. Without a shadow of a doubt THE best mousemat I have ever purchased. I've had it for about 2 months now and absolutely love it.
Ive got one in my shopping basket at scan right now, good to know it going to be worth it. I lived for far too long using a thin A4 book its just not right.
Dont have one of those (a razer exatamat I think) but they are certainly worth it... unless like at my office you have a faux wood desk - which is perfect.