If it's anything like the Surface for the Pre, it isn't slippery at all. My girlfriend has a Surface on her Pre, uses it while jogging and it never slipped.
I have this case and the holster the case when I first got it wasn't as sturdy but after some use I really like it. Sliding the screen open is a lot easier. Also its a bit slippery. It has a nice soft touch feel. Not too slippery but a naked torch felt a lot better. Overall I'm satisfied with it.
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