If you're reasonably patient, friendly, and pay attention, even a mono-lingual foreigner like Brad…read moreP. or myself can have a great experience with Europcar!
Like Brad, I had reserved a particular model but was told it wasn't available and offered an upgrade. This is to be expected when renting a car. If you want a guarantee of a specific model, you need to reserve accordingly. It is a vehicle fleet, not a candy store, and the terms are quite clear about this. Faced with this potential disappointment, I asked if I could wait for one matching my preference to become available, and the staff were very accommodating. I waited no more than 30 minutes and got exactly the vehicle I sought.
Namely, a VW Golf VII TDI. It was in excellent condition. Its navi was set to English for me already, and they included thoughtful small touches like a parking time card (v. useful when parking in German city streets) and a snow/ice scraper. The car was great fun to drive and had fantastic fuel economy.
Later, when I needed to modify my return location, I called Europcar support and had a fantastic experience. The rep spoke flawless English and went out of his way to help make sure I knew where the new drop-off lot was, as it was at the dense and potentially confusing Cologne Hauptbahnhof. Europcar didn't charge me any extra to change my drop-off location (both the reserved and revised return locations were different from the origin at Frankfurt.)
What was originally just a practical, flexible form of transportation for me to range around the Rhineland in became one of the unexpected pleasures of my trip. Vielen Dank, Europcar Frankfurt!