Costs.... many blood, sweat and tears? I am still thinking of making a 2nd one because it supprised me that much but the time and efford takes a lot although a 2nd one will go much easier. Indeed the design with the longer tapered pressure plate, all parts in shiny aluminium and the modding to lightweight is making the look and today the average customer is sensitive for that.
Well.... maybe there will be a production. As my sponsor has his own machine shop with several 7 axle CNC lathes/mills it is just pinuts to make it, I just figured out the parts in a drawing. The aluminium clutchbell and gears is also his production.
Speed is only fiction but a 130+km/h MRS4 is for real.