I've used it and it is ok but for what it is, kind of expensive. Personally, i just use either Zoo Med aspen or Zoo Med Forest Floor aka cypress. Both pack down better so snakes cant hide poops under it and i dont have humidity issues to begin with.
You can also look into Reptichips which i've used too. That stuff works ok too but with it being a bigger cut of substrate, snakes tend to be able to hide poops and pisses under it.
And those who say Reptile Prime is dust free are wrong. The stuff puts out as much dust as either of the 3 other substrates i've used if it is allowed to dry out.