It's all about perception and where the market believes revenues will grow to. There is a private company in the 3D plastics/polymers space (Carbon 3D) which recently raised US$100M at a valuation of US$1 BILLION and has zero revenues.
I'll stand by my opinion that RBO is cheap at 10c. The market will ultimately decide.
RBO is no potential billon $ company but at a $20M valuation it's worth a punt IMO.
