nissanlove, I bought 17" 350Z rims off ebay for use as my winter rims here in Toronto and put Continental Winter 4x4 rubber on them. Rims plus shipping and border taxes cost about $550 Canadian from Georgia. The front rims are 7.5", the rear's are 8", I'm sure the same as the 350Z 18" rims. The bolt pattern is exactly the same, and the offset is either identical or close enough that you cannot see a difference. With 235/65/17's, they fit in the wheel wells nice, and look really awesome. You could easily upsize the rubber, but I plan to do that with my new summer rims.
I plan to sell my 18" SL rims, because I have bought SE rims off ebay in California for US$400, which is about the going price for a good set with no damage including centre caps. These wheels have been dropped off N/C for me at LA wheel and Tire for a brand new Millenium Black Chrome finish to be applied, which I am awaiting delivery on. Unlike regular chrome which is dipped, this is actually sprayed on and has far greater durability, and equals chrome plating in shine. I chose this revolutionary new black finish, which is actually more like a subdued Gunmetal, so it would not be quite so "bling-bling". The cost for the Black Chrome treatment was $810.00 Canadian, including chroming the centre caps, shipping to Canada and 3 year warranty. I expect there may be another charge at the border, but the wheels are coming to me clearly labelled only for "chrome plating of customers own rims", so it likely won't be much. My total cost, about C$1400.00 for the rims, which is still far less than the dealer, still Nissan quality, but totally unique. Will post pictures once they arrive and I get my "back-ordered" Toyo rubber for them. Hope this info helps in your decisions. Cheers!:7: