I have 22s on mine, run them at 35lbs and light load setting, I'm perfectly happy with the ride and performance.
The best way to know though for your personal preference is to go test drive F-Paces with 22 and 20 inch wheels and tires. If you are serious about buying one the dealership should allow you do to that. Make sure the 22s are set at light load and only 35lbs cold especially in sunny cali since the tires will heat up quickly. Decide based upon your ride.
Handling is markedly better, as JWreck stated with the 22s. Drives more like a car then a SUV/CUV. If that is what you are looking for go with the 22s.
If you are getting an F-Pace with Dynamic suspension, test that out as well as normal and eco during your test drive.
If you are truly looking for performance I think you will be happier with the 22s, and they look better on the car as well IMHO. If you want a true luxury SUV and don't really care about precise handling go with the 20s, the car will ride softer, but won't be as sporty, but it will still handle better than most others when it comes to SUV/CUV's.