Howdy!
21" wheels and up are really only 'tolerable' on perfect roads and with air suspension. The unspoken issue is that the Q7 is famous for 'eating' tires in those larger sizes, and of course ride poorly due to the short sidewall aspect ratio, in the process of tearing through the tread. The Q7 is a very heavy vehicle.

The guy who opened the thread is from New Jersey, and has been through many, many sets of wheels that he's damaged. Short sidewalls equals bent wheels on bad roads.

Sure, I also think they look great on the car and in pics, but they offer poor ride quality, costly buy-in w/new tires required to fit XL sized wheels, it will eat tires, and you will be getting 'curb-rash' and eventually bent wheels, unless you just leave it parked at home. Haven't you ever wondered why concept cars/trucks made for attracting attention always have ginormous wheels, but the production vehicles based on them for use in the 'real world' don't? Choose carefully.