I didn't finish more than 10% of this book. Following the games was painfully slow, and that's without having to deal with the many typos that someone had corrected in pencil in my library copy. The openings are not common today, and the games too good to be relevant to me.
45 years have passed since this book was originally published, so any remarks about openings should be viewed with a healthy dose of skepticism. Since this edition, computer analysis has become much more popular so it's probable that some of the variations cited by Mr. Reshevsky would not hold up under such scrutiny.
A major problem with the book, however, is the number of mistakes in the transliteration from descriptive notation to algebraic notation.
Still holding up well, however, are Reshevsky's comments on positional elements of chess; in this context, he is in his element.
All in all, though, there are probably better books on positional chess available that have been written since the turn of the 21st century.