I understand how offset works, completely. I have owned a car where the difference between 38 and 35 mattered. At 38 it was slightly touching the inner arm at 35 it cleared it. I want to go 35 but if its a difference of even the slightest rub to the fender i will go 38 as long as it doesn't rub on the inside.
This question is more for people who run or have ran 8 inch wide wheels and can be completely honest that their tires dont rub at et 35.