You can measure the distance between wheels and fenders to determine what thickness of wheel spacers to install. Maybe you can try what I installed.
They can customize the thickness and data that I want, so that I can install new tires with different data, and the customization time is very fast, just 1~3 days.
They have aluminum alloy 7075-T6 and 6061-T6 options. 7075-T6 will be more expensive but better in quality. In fact, 6065-T6 is good enough. Its tensile strength, yield strength and elongation can support our normal use. And its lugs are grade T10, studs are forged grade 12.9.
VAG put a massive amount of R&D into this latest-generation quattro system, the individual motors in the e-tron deliver a precise amount of torque to each wheel depending on steering angle, vehicle speed, and other factors, and people change the width?
I would argue it doesn't "improve handling" and urge caution, but I suppose people have done crazier things to make their cars look cool.