Actually, I found the movie to be a great homage to the time period. As a watch collector, I always look to see what the main characters in a movie are wearing. I was not disappointed! The Brad Pitt character was wearing a 'Bulls Head' chronograph which would have made him ultra cool at the time. It was no 'Paul Newman' Rolex but still in line with what a Cliff Booth of that time period could afford.
And for you Sharon Tate fans, this was probably her best work: