3 foot (or 1-meter) hexes are a little better, since that's a (longish) human stride, and hexes pack more tightly than squares, but I see your point. I, too, much prefer Spirit of the Century's zones, or other, fuzzier definitions of distance ... especially if every character is about the same speed. Chases reduce to a "stat vs. stat" roll, or similar, adjusted by differences in speed.
If you're using minis and tactical maps, a tape measure works too, although it doesn't seem as convenient as pre-measured hexes or squares. Pre-measured sticks or strings, for each character's maximum movement, might be quicker, or not.
"On two occasions I have been asked [by members of Parliament], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question."
- Charles Babbage (1791 - 1871)