I can confirm that for me the laggyness seems to be triggered by preview.app especially with complex pdf files.
I work a lot with architectural drawings and my macs become almost unusable when trying to open such drawings.
I can reproduce the issue on my:
MBA mid2013
MBP Retina late 2013
iMAC 27 2013
On Mavericks the zooming and scrolling of the files works just smooth as butter.
Here two exemplary pdf files, I would like to receive some feedback specially from the people having no issues:
https://drive.google.com/folderview?id=0BwQwR5XgWLk2MXJUREZxUHFvVm8&usp=sharing