There's something odd about the review of the Chopin bio by Walker. Added at the end of it is a review of another book, one that is specifically about a piano Chopin used for a time in Majorca. From the review, you'd never know that Chopin had a decent Pleyel upright for part of his time there, which is discussed in the Walker book. It's almost as if the reviewer forgot the first and primary book being reviewed. I don't know if there is an reliable information anywhere how much composing Chopin did on the crummy, locally made piano that is the subject of the second book.
I'm a little over 500 pages into Walker's Chopin bio. I'm not as impressed as I had hoped I'd be - unlike the reviewer, "magisterial" is not a word I'd choose to describe it. I'm finding I don't necessarily trust Walker about what matters, and how much it matters, and whether it is possible to reach conclusions about things.
But, on the other hand, I'm not sorry I am reading it. It's the only bio of Chopin I've read (or am likely to read), and the vast and varied amount of material collected in one place serves its purpose. There are all kinds of interesting facts that I'll remember. For example, I had no idea that Chopin and Liszt had publicly performed a four-hand sonata by Moscheles, on at least two different occasions. I love stuff like that.