I do not believe there is any particular "market" who preferes anything. This assumption is based on "European Taste" or something like that. I tell you, there is no taste, there is just diamond vendors who sell what they have always sold. Then they call it " European Taste".
When I started to sell H&A it was immediatly accepted by my customers in Finland.
There is a big market for H&A ( or ideal cut) in Europe, it only needs to be marketed here.