Poe's character Dupin shines as the archetypal detective Poe defined for the genre. To this day that archetype still holds.
Of the three stories in which Dupin is featured, The Purloined Letter is certainly my favorite. You can see Poe's usage of a brilliant detective and a less brilliant friend who needs the reasoning explained as a mode to tell detective stories in Sir Arthur Conan Doyle's stories, most notably, among many others. If I remember correctly, Sir Arthur Conan Doyle also used the loud noise outside a window to help solve a case, once.
The story is so believable that one can still see it happening today, even with all our sophisticated search and forensic practices. All to often folks still forget to look at the simple and obvious.
That's a great message to take from it, and very true, I think.
Jackie