But tire and rims go hand in hand. If you +n or -n (too keep approx wheel diameter), you change the weight of the wheel which has a different mass and inertial. Multiply that by 4 and considering that it's a rotation mass, I'd say people familar with their cars probably feel "something different" but probably can't tell exactly if it's worse or better. People say 2lbs off the flywheel makes a huge difference.

I'm not saying it's an accurate feeling.

So in summary:

- can you feel it? maybe
- can you identify a help/hinderance? probably not
- will it affect gas mileage? depends on tires too
- will it affect 0-60 times? depends on tires too