I live in an area with a LOT of ASU grads/fans. A group of 20 season ticket holders for both football and basketball on my immediate street.
They are well informed and very supportive of BYU except on the occasion the two schools play.
UofA fans in my neighborhood... that's a different story, but I've always found the Sun Devils have been respectful. The ONLY thing I don't like is when they pull out their "Mormons for Devils" shirts... I just personally don't like how it brings in a religious undertone.