Just out of curiosity, what did you mean "unpleasant discussions in
this context before?" As I am new to these devices I am curious about
their history.


Do a google search. But rest assured, the discussion I am talking about
had nothing to do with the devices. They were typical usenet excesses.

If you want to know more about these devices, I'd recommend the
articles in Aviation Consumer as a starting point.

--
Thomas Borchert (EDDH)