I have been frustrated with this ever since I bought my 15" rMBP last year. I am a product design student and when I view my PDFs in Preview it is extremely choppy. I understand that they are vector graphics and so they are being rendered on the fly. But, Safari seems to handle them okay. Is there a reason Apple hasn't applied the same scrolling engine from Safari to Preview. I know I am probably dumbing this down but I feel like it would be as simple as a cut and past code job. Any thoughts? Also, is there anything an average consumer like me can do to get Apples attention and have them fix this?