Sherlock Holmes is without a doubt the best detective in the world. At least for me. I like Hercule Poirot as well and there are certain similarities between the two gentleman. For one: they have style and nicety :)
But comming back to Sherlock. He is not the nicest guy you can imagine. He is very self-confident and sometimes arogant. He likes to show off at times proving that he has an exeptional mind power and unique skills. That's particulary visible when he deals with the police. However, he allows the police to take credit for his work and does not want to be famous. Only thanks to Watson's articles he becomes a well known private detective.
He doesn't have many friends but he also doesn't seek them. He values Dr. Watson and Mrs. Hudson and it seems that they are the two people who can actually put up with him and his difficult character.
I like him because he doesn't take NO for an answer and he doesn't suffer fools gladly. He thinks and says what he wants and makes his own mind about many things. He is rarely influenced by others and although he is not a people's person he will do anything for those he respects. He is bold and impertinent at times but somehow charming as well. And when you see his work and his techniques you cannot help but think that he is a genious. So maybe he has every right to be arogant :)
Brilliant Benedict Cumberbatch!