I live in Toronto and waiting for my 2010 IS350 to arrive hopefully by the end of the month. I've been doing some research on winter rims and tires and have decided getting the Toyo Garit KXs 225/50/17 all around. It was recommended based on the fact that I could rotate them in the future and get better life out of them. (Stock size all season tires are 225/40/18 front and 255/40/18 rear). After doing some calculations, the speedometer would be off roughly around 2% which is acceptable from what I know at least. As for the rims, the shop I went to recommended MSR rims style 068 which are 17 x 7inches having an offset of 35mm. I asked the store owner on more than one occasion weather this would fit and he was certain. From what I've heard, the brake calipers on the IS350 are large and not all 17 x 7inch rims would fit. My first question is, is this true? and if so, should I be looking at 17 x 8inch rims instead? Second question..if the brake calipers are too big to be contained by the 17 x 7inch rim I mentioned earlier, would wheel spacers do the trick? Any help would be GREATLY appreciated!!