I've recently got back into James Bond after more years than I care to admit to and was immediately reminded of why I liked Ian Fleming back then. He has a flair for description, especially when he's dealing with exotic locations (many of which have changed out of all recognition since the 50s when he wrote the novels. His action sequences are completely realistic and have authentic consequences, as opposed to the "take a bullet, shrug it off" style of some modern authors.
As per my headline, this is a completely different beast from the Roger Moore movie of the same name; this Scaramanga is nothing like the smooth, suave Christopher Lee character (excellent though he was). This Scaramanga is an all-out thug, double-crossing everyone in sight and scratching around for cash to pay off his more persistent creditors when he can't just dispose of them. It rattles along at a fast pace, though there are so many heroes and villains packed into some of the middle scenes, it's hard to keep track of who is Mafia, CIA, KGB and assorted other organisations; you have to keep leafing back (not as easy on a Kindle, incidentally; any chance of a multi-page thumbnail diplay, Amazon?) to check their affiliations to assess the significance of their actions from time to time or the plot gets away from you.
I believe this is one of the less-read JB novels but it shouldn't be. I wouldn't suggest it as an introduction to Bond, though - read the novels in sequence starting with Casino Royale and the character makes much more sense as he develops.