W.N. James, a great admirer of Berbiguier, writes in his book A Word or Two on the Flute (1826): 'These [duets] have never been published in England; at which I am somewhat astonished, as the composer appears to have marshalled up all his energies to render them superior to the rest of his duets'. Vester, in his foreword, adds: 'The duets not only draw attention to themselves because of the unusual keys: F minor, B-flat major and C minor. They are moreover full of emotion, at times dramatic, nervous, at others catchy or elegant, in a manner that is rarely found in duets.'
Difficulty level, roughly compared to ABRSM exam grades. 0 is beginner, 9 is advanced (beyond grade 8).