I just received 2 of them, one of the rough ones, and an ocean one.
I really like them.
They are a kind of canvass/fabric, not too thick, painted and textured on one side. They give a nice 3D feel, since the terrain doesn't look flat beacuse of the 3D texturing, and there are not 3D features rendered in 2D (like a fallen tree or such printed on them). For example, the sea one has very small waves – definitely there, but shallow enough that a ship model would not be "raised" if put on it.
They should work well with elevation under them, even if, since they are not as thick as a neoprene mat, I suppose for best effect you should put under them a continuos support, not a "spiky" one, or there could be "creases" or "emptiness" in it.
Like in, ok with a curved pillow, not sure about a glass turned upside down to make a peak. They are not solid enough to provide support on themselves.
I believe they work well on any scale, there are not features that stand out as being one scale in particular.
They are on Etsy, not Ebay:
etsy.com/it/shop/WarSigil
I am out now, will try to post a picture of them (maybe one with elevation under it too) one of these days – if I can find out how to post pictures here :-)
Edit: Just to be precise: I am describing here the Rough and Surf mats, I don't have the Turf ones, that are quite different, because of the "grass" effect – even if I suppose the canvass base is the same.
goes to sea with the Terrain Mat.
