Just put down
The Beast 666 and what are my comments?
While Crowley's life is absolutely worth retelling, at least because it's so incredible, John Symonds make a mediocre work of telling it.
He tells a lot basically worthless episodes in incredible detail but omits whole important episodes (for example when Crowley, out of rebellion against his mother, decided to be damned at all costs) and, quite often, his writing style becomes slow and cumbersome.
While this may be the definitive and most detailed Crowley biography out there it's surely not the best to understand the man and his tenets of faith. Recommended only if you have the time and LOTS of patience.
_________________
Fas: Ite, Maledicti, In Ignem Aeternum.