How can I say this?
Well, I say this because I read some of them and am not impressed. He may be a great trainer, but I find that his books are not good. On endgames there are better books like Muller/Lamprecht Fundamental Chess Endings, or Silman Complete Endgame.
Example is his chapter one of the analytical manual : combinative fireworks ! which is just an overview of complex moves clearly resulting from Engine analysis. It is complex yes, but what does it teach?
Capablanca, Euwe, Lasker, Watson etc... are just better teachers.
It is too easy to say that his books are for the better players only. They are not well written. I play in a club with GM's etc.. and nobody really enjoyed these books.
it doesnt matter you enjoy or not. what does matter IS = what you can learn about those specific chess books.
Chess Lesson by Popov is a good alternative. Popov is well known trainer in his country and has produced GMs. Example of his topics are too much calculation and not calculating enough.