I thought that substrate looked familiar!
Okay for people who don't know about critter country: its commonly used for rabbits as rabbits have the same problem beardies do, which is eating their substrate and getting Impacted Bowels from it. Its made of mostly dried grains, with a bit of paper in it, if I'm not mistaken. Since its made out of grains it is safe for rabbits and such to eat.
But grains have alot of fiber, so just to warn you Dogitude, he won't be able to fully digest it if it is eaten. Not to say he'll get impaction in small quanities, he'll digest what he can, and what he can't digest he'll pass easily (that's what fiber does, it can't be digested and makes you have more fecal matter, but strengthens your digestive system). However if he eats too much (more than 2 mouthfulls a week) he will get impacted, if not just extremely constipated (what I mean is he can poop, but it takes a lot of effort).
Also Critter Country works alot like cat litter, absorbing the liquids and making the solids less odiferous. However this might pose a bit of a problem. Make sure that you spot clean as often as possible (2 times a day or so) and I suggest you change it completely, weekly. If his excrements get absorbed into the substrate, bacteria will grow causing your beardy to get sick.
But anyways, if you keep up with the spot cleaning and the more-then-often changing, and he doesn't eat much of it, you should be fine. Congrats on finding a pretty good substrate!!! (if he starts eating the critter country alot , have him checked for an iron defiency-k?)