You could say that the Pat Metheny Group (PMG) combine the best features of 20th-century rock and jazz: they put on a big, loud, value-for-money show, with note-perfect lighting cues, and they are awesomely talented performers, capable of producing endless streams of invention throughout a long evening. But you could also say they combine the worst excesses of the genres: an over-amplified, stadium-style presentation full of smoke, light and humourless bombast where everyone plays for too long without saying much. In everything he does - from little throwaway gestures on acoustic guitar to the vast richness of his body of work - Metheny shows he has a musical brain the size of a planet. Yet when he cranks up the volume, there is a shrillness to his sound that works against the sophistication and subtlety of his ambitions.

This hugely popular band is a six-piece: it has Metheny on guitars, Lyle Mays on piano and a battery of keyboard synthesizers, bassist Steve Rodby, drummer Antonio Sanchez and multi-instrumentalist/singers Cuong Vu and Richard Bona. They play several old PMG favourites and plenty of new songs from Speaking of Now, the new album. Metheny also delivers solo pieces, duos and a straight-ahead version of Jobim's How Insensitive. The show lasts three hours without an interval.

There is a vocal quality to the music written by Metheny and Mays; you can see why they like using singers. At times the word less vocals enhance sounds that are already voice-like. Occasionally Bona and Vu take the melodic lead with a kind of smooth scatting. On Her Way sounds like a Beatles or Crosby, Stills & Nash song to which they've forgotten the words. Yet the piece develops into a quiet three-way improvisation for vocals (Bona), guitar and drums - inspiring and musical.

Bona's appearance with his own band at the 2001 London Jazz Festival was a beautifully structured, five-star gig. His role with Metheny shows only a fraction of his talents, but it is likely that the alliance will be good for both musicians' careers. Vu was an equally smart recruitment choice. His impressionistic trumpet/electronica feature on Offering tested the patience of the fans at Saturday's packed show, but it was a high point - a moment where the PMG engaged gleefully with the spirit of the new century.