The nationality of Gaetano Donizetti's La Fille du Régiment is as confused as that of its eponymous heroine. Written by a homesick Italian expatriate for that most Parisian of venues the Opéra-Comique, it both continued Donizetti's Italian colonisation of the Paris opera scene (much bemoaned by Berlioz) and showed him adapting his style to the conventions of French theatre.

In last night's Royal Opera performance, the layers of Franco-Italian intertwining were at their most tangled in the singing lesson of Act II, in which an Italian soprano (Patrizia Ciofi) is cast as a French girl (Marie) making a hash of singing a tune which we are told is a bad Italian melody, the gag written knowingly for a French audience by the very Italian Donizetti, the whole scene in this case under the direction of the French Laurent Pelly.

This production has been highly successful in past runs with (the French) Natalie Dessay playing the sulky teenager Marie to perfection, and there will certainly have been those who doubted Ciofi's ability to match her standard. But match it she did, although with a voice that sounds quite different. Ciofi's diction is less clear than Dessay's, but her voice is rich and creamy smooth, fully in control and in tune, albeit with heavy use of vibrato at the top. As I might have expected, she comprehensively nailed her big solo numbers, but what surprised me was the quality of her acting: she threw herself with relish out of "great Italian diva" mode into the character of the tomboyish Marie.

Two years on from first singing the role of Tonio at Covent Garden, Colin Lee has turned into the finished article. It's not as angst-ridden a role as a Nemorino or an Ernesto and Lee sings it with elegance and good humour with a voice that is light, clear and confident. He negotiated the famous nine high Cs of Ah Mes Amis with ease - the first eight in a sort of yodelling phrase which echoes Tonio's Tyrolean roots, the last a sustained close designed to bring the house down. Tonio gets a succession of lovely romantic melodies: Pour me rapprocher de Marie was the one I enjoyed most.

Ann Murray was in particularly fine comic form as the Marquise de Birkenfield who spirits Marie away from the regiment to her ancestral château, particularly impressive as she plays the piano for Marie's singing lesson while singing her own lines and staying thoroughly in character.

I love Laurent Pelly's setting, and seeing it for the second time gave me a chance to enjoy some of the detail. The soldiers march about on mountains made of giant crumpled up maps of Europe; piles of regimental laundry are lying around everywhere; the weirdness of the Marquise's château is accentuated by a distorted perspective; the ballet interlude that precedes the second act is entertainingly populated by maids frantically dusting everything; giant panels descend with a map of France, a "barometer of love" and a crowing French cockerel; there's even a tank on which Tonio arrives to rescue Marie at the end. But revival director Christian Räth also deserves plaudits: the acting performances from the whole cast were excellent and the movement around the stage was crisp and incisive.

But somehow, in spite of all these good things, I didn't feel that this performance quite ignited. I suspect that this is largely a question of taste in orchestral style: Yves Abel was clean, precise and just a shade restrained, which works fine for the set piece arias where it makes room for the singers to take over, but left me feeling slightly flat in the orchestral and ensemble numbers. It's nice to get the clarity, but I think this opera works better with a more rumbustious Italian style. Another false note, for me, was the gimmick of having a former Cabinet minister playing a caricature of herself - Ann Widdecombe carried it off adequately, but the script she was given was fearfully predictable, with the best gags (which I won't spoil) being provided by the surtitlers.

So I'd recommend this production warmly on the basis of the singing and acting performances from everyone and of Pelly's wonderful setting - even if the whole evening didn't quite hit the heights of which this opera is capable.