OK, I am puzzled with why the taokey saying that. But anyways..
I run an FR. and I run 16"x8J rims for both, the front and rear. BUT. normally, FR rims tend to be different in sizes, slightly wider for the rear than the front. e.g.. 16"x8J (F) 16"x9J (R).
Anyways, there could have been many reasons why he said you could run those rims you wanted. PCD maybe? or Offset?