I've seen some imitations of it, considerably cheaper but they look downright rickety.
Holds wood well from small 2" to larger 8" or so, after cutting a few bits, it weighs down the frame so to speak.
Have not had any problem from it moving about once set up, seems once you have a piece of wood placed in it, it holds it well.
If making your own, I would offer that you make it a few inches higher for better work height, and the base another inch or 2 wider if you felt it was needed.
Apart from that, its really improved the way I deal with small lots of smaller wood.
T