With Euro Delivery, your car will be a USA spec car; the analog speedo will be MPH. The digital speed readout is easily set to either MPH or KPH. The KPH is really usefull and you can reset it to MPH when your car gets to your dealer.
Factory delivery is excellent and highly recommended if you have never experienced Germany outside major cities or toured along the Rhine. The $2,200 (?) hit and the double wait (for your trip and then for return of the car) are negatives. With the "miles" you need to use up, I'd say "why not". If the new museum is not ready that's also a negative. The "museum" they show you is temporary and minimal. On the other hand the view of the new museum construction site from the dining room (excellent food and wine) where they serve you lunch is memorable.