Benedict is the modern Holmes, so I think it is apples and oranges, and Benedict strove not to use Brett or Rathbone as models but go from canon - he's a young Holmes, so he's a bit more volatile, more anti-social, but Moffat and Gatiss want to have somewhere for the character to go, ie: his relationship with Watson making Sherlock a better man.

I think I've been surprised to learn that many younger people don't know of Brett's Holmes! So it's good to introduce them. And I want to crack my ACD open again.