Honestly, I'm of two minds on this one. 
 The first is just how much fun I had running around with a trust fund buddy and the scam, enjoying 50's Italy, and especially the really delicious riffs from so many of the great authors doing their thing in the day, the subversion and the dark twist. I mean, we're all super-familiar with the heroic(anti-heroic) murderer protagonist, and some of us might be extremely familiar with it if they've read practically any mystery novels or watched ANY tv at all... but here it is, one of the first to really start the very popular modern mystery trend from the PoV of the sympathetic murderers. We'll ignore how much we love Richard the Third or the long line of True Crime novels or the Penny Dreadfuls, for now. This is the world of anti-hero worship, after all, thank you Dexter and Darth Vader. :) 
 So yeah, I had a really good time with this. I remember watching the movie and have a great time with it, too, in the theater. Little did I know that I was missing out on great books, too. :) I'm making up for lost time. :) Mistaken identities, con games, great play-acting, opportunity, and, of course, seeing the bad guys win. What's not to love? 
 And so I go to my second mind. 
 Closet homosexuality. This novel, with so many others of the time including movies, always made the bad guys homosexuals. This is trope made tripe and it's as stale as it is insulting and almost entirely distasteful to modern readers, if it wasn't already so to people back then. I chose to read it as a buddy novel gone really wrong instead of thinly-veiled homosexuality, and I enjoyed it more, but the question still remains. I can write it off as a sign of the times or general ignorance or a cynical pandering to popular conceptions, or I can think again and be sad that such an otherwise interesting and cool novel should now be relegated to the back-shelf of history because of the implicit homophobia it exhibits, even if there was never an explicit hate comment. 
 I'm willing to be generous, though. One doesn't toss out decades of literature just because the societal norms of today has changed significantly from those of our grandparents or great grandparents. We twist our noses and complain of the stench, but we still enjoy what is GOOD about what we've just read. That's where I'm standing, anyway. :)