We have several varieties in San Diego County, none of which have fruit that I would seek out. The traditional uses of the fruit were to trigger constipation or for use as a laxative depending on stage of ripeness, or at least that is my understanding.
The wood is quite beautiful, and the bark that is shed off each year makes an excellent tea that tastes similar to raspberries.
There are several types, some have several trunks emerging from a single burl, others have typical tree trunks.
I don't think they will do all that well in Austria, as they can handle very limited frost. If you want to try,
Madrone may do well for you, it's a similar tree in the Heath family that grows near Napa Valley.