I`ll agree with all above mentioned, but I`ll add my 5cents. The average home internet in Germany sucks hard and is crazy expensive, currently working with German company, when guys work from office its okay, but as soon as they go home it becomes awful π, and we`re talking IT guys π. And yes, the best option for you guys would be to rent a server somewhere in between to host the game for you. This would half the distance lag, and you will then only be bound by quality of your own connections.