I am sure this aircraft has been discussed before on
Prune but it was cost and the absence of launch orders that killed it. The tip jet issue was overcome and in any case they were only on for a very short time during takeoff and landing .Engineers still admire the concept and visit the Helicopter Museum to study the dynamic system which is on display there,together with examples of the tip jets and the silencers,one complete blade and a section of the cabin.
The book mentioned is also available too.
The museum has recently been refurbishing one of the blade sections and has kept the original skins with a view to selling pieces framed with a photo and certificate of authenticity to raise funds.
So if you would like an original piece of Rotodyne on your wall,pm me or write to the museum!