SHMP has patented, scalable technology allowing for world wide and additional specie growth. This is where the mega dollar potential is...would not be surprised if there is a buyout/ merger with a major food company in the near future.
Do your DD, I looked at RDM months ago. As far as I could find they are not a high density system. Also 70-90% += 80%. SHMP is looking at an average survival rate of at least 10% more than that. There is also a company called Ralco that licensed what they call a raceway system from a Dr. Addison Lawrence and Texas A&M. While it is a solid system the cost to build is far more and not as easy to scale than SHMP's system. As far as a survival rate for them I couldn't find one so it can't be all that impressive.
The key is density. The lower the density the easier it is to have a low mortality rate. SHMP uses a high density stockin and has experienced virtually no mortality.