Having been to both countries I can tell you that the cultural and language barriers are A LOT lower in Germany. Most Germans know some English and most who do are more likely to use it than the French that do though using some German with most gets you a little further. The culture is a lot more familiar with some major differences though not the huge gulf that you find with Japanese culture, it is definitely very 'western' versus 'eastern'. There are a lot more foreigners around in Germany which helps with the tolerance and I got the sense they were more accommodating in Japan where I felt like I was just tolerated in many places, maybe that was me though?!
And if you get sick of Germany it is a lot easier to travel around Europe than escaping Japan, riding the rails is very easy and convenient.
I know a few folks in Stuttgart and the HQs and while most work hard there is definitely a different climate when it comes to work than you usually find stateside, usually a bit more relaxed. It can be office dependent but that is the general climate with most encouraging their office mates who are only there for a 2-3 year tour to enjoy it and see Europe, longer vacations are normal in the summer months. If you end up losing leave while there you are doing something wrong.
I have to say though I am impressed, how much time have you all spent in CONUS since TRACOM? Coming back to the states might be a shock to you all after so much time overseas.
