When my dad bought me my first pair of dress shoes in 10th grade (black Rockports), he gave me this advice about buying/trying on a dress shoe: if you had to, do you think you could run a mile in them? If not, don't buy them.
I only ran maybe 50 yds. today in my AE Hanovers (to catch the bus), but I'm glad for his advice. They felt fine.
You never know when you'll have to break out into a run.