So, I have put ~200miles on the tires at 60psig and have notice what SEEMS to be better handling around corners and a few more seconds longer at coasting. I haven't notice any decrease in braking(I don't remember what normal braking is like). The bumps and uneven ground are very noticeable but tolerable.
The Cornering is subjective - what seems to be handling better may be do to the car skidding and me not noticing since I don't hear the wheels chirp, however, it does not feel like the car is skidding or drifting it feels like it stick to the road which is contrary to what I would of thought.
I am referring to the STOCK SPORT DUNLOPS that come on the FIT.
I have to agree with
mahout that the tire compound has a lot to do with traction of a car. You don't need a wider tire for better auto crossing but you do need a sticky tire which will come down to proper psig and what the tire is made of.