This is the first Hunter S. Thompson book I've read, though I'm aware of him by reputation.
I'll probably give another one of his books a go, but this one didn't live up to my expectations. It's not that there's very much wrong with it, just that the story didn't grab me. It reads a like a loosely amalgamated collection of journalistic stories, which I suppose it technically is. First one thing happens, then a chapter later another different thing happens and all that links them are the fact it's the Hell's Angels doing both those things.
I also get the impression that you'd find the story more engaging if you had some vested interest or context. Say you're a biker yourself, or your parents had their town trashed by the Angels in the 60's. Problem is, Thompson's writing style sort of assumes you'll have that context. If you were ambivalent about the Hell's Angels beforehand, this book's unlikely to change your view. They almost come across as a bit quaint; perhaps we have bigger, or different, bogeymen now than we did in 1965.