Surprisingly entertaining if you are looking for some dumb fun and probably the only Guy Ritchie film that I have tolerated. Kills most of the source material but at least it understands the importance of the central Sherlock/Watson relationship being like an old marriage.
I remember hating it more when I first watched it but that could be due to the irritating Gatiss/Moffat re-imagining of the stories. It tends to go for Ritchie's forceful way of trying to be the coolest cat in town but the music, costumes, scenography and chemistry between Law and Downey make it less cringe-worthy.
5/10 Sherlock this is not. More like Jackie Chan meets Marvel superhero movies in victorian england, with bad CGI. Entertaining and witty at places, badly written and bland at others, I miss the old Guy Ritchie. Not a bad movie, but skippable, you wont miss anything great.