Had been assuming I would go with 19s but look at this Velgan set up! Will 20 inch fit seamlessly or will it rub? Also is this lowered or does the 20 inch just fill out the stock suspension this well?

http://velgenwheels.com/project/infiniti-g37s-sedan-velgen-wheels-vmb5-matte-silver-20x9-20x10-5/

 

It's lowered in the 2" range. At stock height 20s will look a bit off as the fender gap appears even larger than it really is. I would stick w/ 18s at stock height or 19s at most.