Other comparable adapters are the HDx35 from Abel Cine or Sonys which both cost around $5,900.
The MTF adapter sells for $1,875 because you have to use the 2x extender on your 2/3 lens.
The MTF adapter has a 1.5x conversion factor which when combined with the doubler gives a focal length conversion of 2.5x, this is almost identical to the 2.5x conversion factor of the HDx35 and Sony adapters. The difference is that the MTF makes use of the 2X magnifier built in to many lenses to do some of the work. This keeps the cost of the adapter much lower.