Has it really been two years since I started learning Japanese at the VHS? Looking back, I guess it would have been better to join one of the intensive courses at the university, since the pace at the VHS is quite slow. The problem of the VHS is, that it has the same holidays as regular schools. So there were weeks where there are no lessons at all and even if there are lessons, there are only about two per week maximum.
On the other hand, the teachers were very nice. Unfortunately, the options for learning Japanese in Hamburg are quite limited, there are probably more options available in Dusseldorf.