This is a wonderful instrument. Really. My heart goes out to the people who worked on it, and whose work was let down by a few bad decisions and bugs.
Before I ask gear4music to take it back again I wanted to document some of the bugs and weirdness. The fingerings around crossing the octave are not documented in the manual (perhaps to avoid putting buyers off?), so for your convenience, here they are, showing what the middle D fingering and the trill keys produce in various modes:
Brisa mode:
middle D fingering: B. yes, a B.
left trill key while playing C: D
left trill key while playing C#: D#.
right trill key while playing C: B flat
right trill key while playing C#: B.
Some seem like bugs, some seem more like bad decisions.
Flute mode, low octave:
Middle D fingering: Low D. This is just awful.
left trill key while playing C: Low D again. Ideal if you often want to trill between middle C and low D, I guess?
left trill key while playing C#: Low D again.
right trill key while playing C: Middle D
right trill key while playing C#: Low D#. Twist ending there.
The middle D fingering producing low D is just a dealbreaker really, but the extremely strange output of the trill keys makes me wonder if it's bugs rather than just bad features. The Brisa mode trill keys producing B I can sorta-kinda get, whereas these assignments just seem completely random.
Flute mode, middle octave:
Middle D fingering: Middle D. This is one of the very few notes that does what you'd expect.
left trill key while playing C: Also middle D.
left trill key while playing C#: Also middle D.
right trill key while playing C: High D.
right trill key while playing C#: Middle D#
This is the same, one octave up, which makes sense, but the trill key assignments are still extremely strange.
Other bugs/misfeatures:
It is possible to get the Brisa stuck in a state in which A and B fingerings produce the same note. You can do this by doing certain cross-fingerings but I can't work out the exact recipe. Changing instruments or turning off and on again seems to fix it. This is awful.
It is possible to get the Brisa stuck in a state in which when portamento is on, going from A to B continues to produce an A. This is hard to duplicate. Again, you need to change instruments or reboot.
Finally... get this... the concert and bass flutes are at the correct pitches but the alto flute is at concert flute pitch! It does seem to be a sample of an alto flute, but it plays the same pitch as a concert flute. It seems impossible that with all the effort that must have gone into the Brisa, that could be a bug. And yet...
I dunno. I just don't know what happened here. If they update the firmware, I'll buy it again.