It's all about preference. You can get Whiz or real cheese at any of Philly's finest cheesesteak places. Some staunch traditionalists will insist that its not a Philly cheesesteak without Whiz, but I disagree. It's not the cheese that makes a Philly cheesesteak so good....it's the quality of the meat and of the bread.
P.S...if anyone tells you that Pat's or Geno's makes the best cheesesteak, disregard their bad advice and get another opinion. They are just the most famous....definitely not the best.
By the way, I see you are from Eugene.....GO DUCKS. It's weird being a Ducks fan in Philly/SJ. I definitely get a lot of looks when I wear my Oregon sweatshirt.