A few things that would concern me:
Title says "stainless steel," but is it ALL stainless, or just the hopper and frame?
Seven images and not one showing the rollers. Are they stainless? Hardened?
That description stating that "the crankshaft can be driven clockwise or counterclockwise." How's that work in a 2-roller system?
The hopper has 1.06 gal capacity and they claim that will hold 11 lbs. of grain? I can get just over 20 lbs grain in a 5 gal bucket, so that hopper might hold 4-5 lbs tops.
If you can get the gap adjusted and the wingnuts hold, it might be ok.