What the papers said:

An interpretation of Haydn’s Symphony No 102 that combined crispness with marked attention to the symphony’s exploratory harmonic palette. It was conducted by Pierre-Laurent Aimard, who, more familiar as a pianist, captured the shimmering, translucent textures of a selection of Ligeti’s solo “Études” and then was rejoined by the orchestra for a delicate, lucid, sinewy performance of Beethoven’s Second Piano Concerto.
THE DAILY TELEGRAPH

Pianist Pierre-Laurent Aimard opened his Prom with the Mahler Chamber Orchestra with one of his rare forays into conducting. Haydn's Symphony No 102 was the work, and his performance aroused mixed feelings. He conducts well enough to make you want to hear him do it again, but not well enough to make him great. The combination of fastidiousness, passion and searching intellectual rigour that makes him so remarkable a player is less consistently deployed when he takes to the podium.
THE GUARDIAN

Haydn’s Symphony No.102 came across as neatly drilled, but not very affectionately played. More rewarding was Aimard’s inward way with Beethoven’s Second Piano Concerto, which discovered unexpected corners of hushed concentration. But the best of this late-night offering came in Aimard’s solo performances of Ligeti Etudes – brilliantly original pieces, alive with wit and intelligence, and an ideal antidote to the Teutonic seriousness of the rest of the evening.
THE FINANCIAL TIMES