My understanding is that the 18" stock wheel is 8" wide in front and back. I see alot of wheel "upgrades" (including the Nismo) that puts a 8.5" in front and a 9.5" in the rear.

1) What does this do to performance? More understeer?
2) How does this affect offset I should look for to stay as close to stock as possible? What offset should I look for if I do go with a 8.5/9.5 combo?
3) So long as I stay with the same overall diameter, I assume the VDC will still work?
4) Are certain wheels "non-compatible" with tire pressure monitor system we have and others "compatible"? I'm hoping to simply swap the tire pressure monitors with new wheels. Will I be able to do this?
5) Stay with 18" or go 19"? So long as I stick to my 19 pound limit (I'm looking for 17/18 pounds), is there a disadvantage to going with a 19"?

Please no "do a search" comments. I've read tons and I've seen very little reference to performance....mainly just alot of "will my wheels rub" questions and "how low can I go". I'm more concerned with performance so any comments would be greatly appreciated.

Thanks in advance.

2004.5 Coupe/5AT/Ivory/Everything but front spoiler/Nismo CAI/Crawford V5