I first bought a 1967 copy of this book in the seventies, which is now falling to bits. So in order to read it for the six or seventh time I ordered a new copy. If you are happy to read it on the understanding that it is a very one sided version of events from Hunter S Thompson - it is a great read. You get a real feel and appreciation of what life amongst the original sixties Hells Angels must have been like, written by a clever and interesting writer in Thompson.
For a balanced and I would guess more accurate view of events you need go no further than original Angel - Sonny Barger's autobiography, in which references are made to Thompsons book, and from reading both - interesting comparisons and view points can be made.
For an acid tripping, drug and booze fuelled crazy view of the Hells Angels, and the best of all in my opinion has to be 'Freewhweelin Frank' by an early Frisco member Frank Reynolds. A great read, mainly I think because Frank comes across as wild, stoned and crazy as most of us imagine these guys were back then,