I will try to be as succinct as possible so as to not drag this out any more than necessary.
These two Mozart releases are intriguing in that they combine major Piano Concertos (#20-24) with the two Piano Quartets and the 3rd Trio, all composed during the two years represented on each 2-disc set. But that's the extent of the attraction. Alas, they are about as disappointing as you might expect coming from a major label intent upon promoting "star power". (Look no further than the cover art to affirm where the primary focus lies.)
Not that Leif Ove Andsnes isn't deserving of "star" status. He's a fine pianist. And he's dabbled in Mozart before (some of the middle Concertos for EMI in the early 2000s were actually pretty good). But I'm just not sure what he's trying to do here. He teams up with the Mahler Chamber Orchestra (which was likely much more conducive to his recent Beethoven Concertos project) and produces Mozart which sounds for all the world as if Mahler himself would have approved. This is Mozart on a grand scale, which is quite out of fashion these days. "Grand" in and of itself isn't necessarily bad, but Andsnes takes it too far into the Romantic period with dramatic heaviness, while SONY fattens it up with overripe recorded sound. One would never know this is a chamber orchestra. It's "big band" all the way, the likes of which Karajan would produce. And it weighs down the tempos and most definitely the mood. Just try getting through Concerto #24, for example, which is downright oppressive.
To be fair, this terrific orchestra plays with a reasonable amount of precision and articulation, but I'd never describe it as "crisp". Or transparent. And tempos are far from "alert". This is serious, pretentious Mozart - with a Mahlerian scale to it. And despite excellent piano playing, Andsnes seems determined to make this "old-fashioned" in all the wrong ways.
Surely the chamber music fares better. Nope. It's almost worse. Not only are all the characteristics described above evident here, but the lack of joy and musical involvement is astonishing. SONY doesn't help, providing an up-close, airless, flat wall of sound, slightly grainy and diffuse, within a reverberant acoustic.
There is one high point, though. Just one. Among 4 CDs packed full of Mozart, we are rewarded with 8 minutes worthy of the master - the finale of Concerto #23. After a lugubrious Adagio, (good lord, I have never heard it this lethargic), the music finally springs to life in the Allegro assai and at last I can describe the playing as crisp, alert and joyful. And with all that surrounds it, it is a glorious moment indeed. But it's but a brief respite.
I know I'm being terribly hard on these recordings. But this is Mozart we became accustomed to (and learned to accept) back in the 70s. Today, in 2021/22, when these were issued, we deserve something more from a modern recording of these masterworks. Something fresh. With something relevant to say. Unfortunately, these SONY releases are none of that.