Thanks to all of you that have replied to my inquiry.
I now get the picture that there are some very good reasons for the NOTAR and they seem to be
a. safety for persons around when rotors are turning,
b. quietness
c. new technology
The downsides are
a. poor performance in hover/high weight/altitude
b. possible extra maintenance costs
c. acceptance of new technology
Once I have some feet on type I will make a report to my findings.