I have read several posts about moving to wider rims. Car is 2008 328ix with 17" OEM wheels. I want to use the OEM rims for winter tires and buy wider rims for non-winter driving. I have read several posts about issues with moving to wider wheels with all wheel drive, primarily regarding the potential for a more noticeable gap between the tire and the top of the wheel well and a harsher ride. Can anyone advise on ways they have addressed this without lowering the suspension? I would like to go to 18 or even 19 inch wheels. I would be interested to hear if anyone had gone to 18 or 19's with AWD (without lowering the suspension) and are satisfied with the appearance and ride. Also, as you move to 18/19" rims, does the total diameter of the wheel and tire actually change from a 17" wheel and tire? Thanks for any help with this.