Are they as good as they look?
Commenting on the beige desert mat, based on my initial thoughts before any modifications or gaming:
It looks fairly simple. Unlike other mats which may be printed, painted or consist of grass glued on paper/canvas, this is solid fibre. Think coir mats, felt, jute sacks or some ugly insulation mat you might stuff somewhere out of sight. This is remotely similar but not quite. It's about 2mm thick, very strong and dense. No woven pattern there, just compressed fibres like in felt. It can be cut with sharp tools, but hardly a chance you could tear it accidentally.
The surface, straight out of bag, is fairly flat. Still, it consists of small fibres with slight texture and colour variation. In this basic shape it might look like hard, brown desert floor or very dry plains. The trick is that you can apply a stiff brush to it, raising some of the fibres to form a grassy texture. That's what I plan to do with mine. Then just drybrush around with greens and yellows to add as much life as you wish. There are two sides (!) so you can keep one side desert-brown and turn the other green, paint both or whatever you happen to need.
So, kind of simple invention. Dense, thin fibre mat with a natural colour. Nothing truly spectacular by itself, but very sturdy and a fine basis for your own ideas. Maybe something similar could be found in hardware stores, at least for this brown version. Nevertheless, Antenociti's price is quite affordable, especially as this comes directly in common gaming sizes and probably lasts a lifetime.
More comments coming after I've tried various tweaks and played a few games on it.