The Buffet is the better instrument.
I'm a saxophone player and only spent a limited amount of time playing clarinet. But I do know that the Buffet is going to be the better instrument.
If she has any aspirations of playing in college, or studying music in college, even for music education, she will need a professional level instrument as her primary instrument.
If she just wants to play in band in college for the fun, and is studying something else, then a quality intermediate level instrument is fine.
If's she's going to be a music major, get ready to start laying down some serious coinage. Because, in addition to her primary Bb clarinet, she will also need a clarinet keyed in A (common in orchestra work), as well as an Eb clarinet, and probably at least a bass clarinet also. If she's going to play in the jazz band in college, she'll need an alto or tenor saxophone, and a flute and/or piccolo as well. Playing woodwinds is expensive, as pro woodwind players are expected to cover all of the woodwind family.
I've got more money tied up in my three saxophones (and mouthpieces) than I do audio gear, or camera gear, and guns. The last saxophone I bought was over $6,500. The next one that I buy will likely be close to $10 grand (will be next year for the 100th anniversary of the brand that I play).