You cannot change font size of pdf which doesn't re-flow!!
sony definitely provides better pdf support as its got pinch zoom option and landscape mode. Pinch zooming is a savior but Landscape mode will only end up shrinking the text. This is what I experienced. But if your pdf re-flows then you will be able to play with it just like an epub file.
I gathered all my notes in word and then converted them into pdf and my T2 is handling them awesomely because they can re-flow.
If you are talking about reading fiction novels then why are you choosing pdf and not epub?
Anyway, sony will be a better choice for you but do not keep high hopes with it. And, I would suggest you to watch pdf experience reviews of T1/T2 before taking decision.