I'm almost finished and thus far I find St Josemaria Escriva's theology and spirituality to be pure gold. I love everything I have read in John Allen's book and from what I've read in St Josemaria's book The Way.
The only troubling thing I've found was a quote in the Allen book about St Josemaria referring to the human body as "the enemy", but I didn't read the context and so I dismiss it on account of charity.
Anyway, I encourage you to buy and read Allen's book: Opus Dei - An Objective Look Behind the Myths and Reality of the Most Controversial Force in the Catholic Church.
For those ready to read this book, take in this word from St Josemaria:
"An hour of study, for a modern apostle, is an hour of prayer." (The Way, 335)