PhD in theoretical phys @ USC or Stony Brook?

[grad]

Hi. I intend to pursue PhD in theoretical physics (applied for fall 2006). I am interested in elementary particle theory and string theory. I am an international student and just obtained a Bachelor degree in physics from a non-US univ. I have two options: Univ of Southern Calif and State Univ of New York at Stony Brook. I am not sure which one to select, even after going through the hp of faculty members and learning about their researches. The USNews ranking places SUNY SB well above USC, but I don't know if I should place much importance on the rankings. Any idea/experiences..?
Thank you.

p.s. I posted the same content as above in the "graduate admissions" section too. But it didn't seem to catch much attention there . So I am writing here again in the hope that more physics-related people visit this section.