Is it any good ?
In my experience, yes and no.
Yes: I really like the size markings on it so that I can roll out the right sheet of fondant to cover a cake. I find it easier to trim the sheet and use just the right amount so as not to have to move an unnecessarily huge piece.
No: I have another mat which is non-slip on the underside, but alas no size markings on it. The Wilton one isn't so it slides around the benchtop more.
If you can find one that has both of the above, I'd go for that.
having used the roll and cut mat, i find it a really useful item. if , like me, you are a beginner then you will find all the measurements easy to use. much easier than getting out your tape measure each time to check sizing etc!! I personally wouldn't be without it now, to me it was money well spent!