In the late 60s at the start of my multi-engine flying training in the RAF my instructor lent me a copy, and said "Read that before the end of the course!". I did and have had a copy ever since and read it every few years. I still find the description about the encounter with heavy icing totally gripping.
FITH was re-issued in paperback a few years ago, so there is no need to pay a fortune - although I would love an original hardback.