Tucson is prettier (surrounded by mountains) and a bit cooler (in arizona climate that is) than Tempe. I find UofA grassy area, lined with palm trees) in the center of the campus to be very memorable. They have a reputable Optical science, MIS and ECE, easily tops that of ASU. I was in Mech. Engr, I don't know the ranking of UofA social sciences.
UofA has about 35k students, ASU about 40k. Regardless which one you choose, with large number of students they're plenty of hot babes and after-hour traps available around campus. If you don't like UofA, you can always join the sunDEVILs.
If you're from out of state and want to save some money, get your lower-level-non-major courses from local community colleges like Pima or Maricopa community college. It was about $60/hr for summer courses.