iPad Mini or Nexus 10 reading PDF textbooks

HI, first time on the forums.

Im going back to school and need a tablet for reading textbooks, I only have $500. I have an iphone and a Macbook so everyone says I should just get the iPad Mini. But the Nexus 10 has a much better and bigger display that I think would be better for reading textbooks but I just don't know.

Any advice would be helpful thanks