First I saw the Beaudin flute as a key that would unlock modern repertoire to me 'early musician'. So the basic requirements were an instrument at high pitch (442 Hz as European standard) and with a C-foot in a modern design. Jean-François Beaudin agreed on building just that and it was an interesting experience to develop the C-foot. He suggested various key arrangements and I opted for the most ergonomic one. To me it was quite obvious that the flute should feel like a normal traverso with the Eb-key as the most important key in normal position. For the lower notes the little finger should slide down the flute. I never liked the solution of early 19th century flutes (H. Grenser) where the finger has to climb up a little mount of keys. For the hand this is a very unnatural movement. As a second option I also got a Quantz-style foot with double d#/eb-keys.
The sound has all the characteristics of a traverso. It can be incredibly gentle and you can take back your playing to almost nothing without the risk to crack a note. The intonation never suffers if you do so. You also can get quite loud, which is obtained best by giving more air with a relaxed embouchure. 'Blowing harder' is not such a good idea, because you loose the richness in overtones and it just gets louder. There are differences in the sound quality of simple and forked fingerings as on every traverso, which is very nice. You never think that it sounds like a modern flute.
To me, who never touched a modern flute, it opened up a repertoire I always wanted to play (Debussy, Ibert, Varèse, Takemitsu, Piazzolla, Franssens) but never worked on, since I don't like the sound of the iron flute, unless James Galway plays it.
Right now I use it to play contemporary Japanese composers: Toru Takemitsu, Toshi Ichiyanagi, Toshio Hosokawa.
Also my all time favorites 'Histoire du Tango' by Astor Piazzolla and Joep Franssens' 'Solo for Flute' are getting ready.