You must have made a really good impression for these guys to pay your flight over for the interview.
If youre destined for GVA, then I would brush up on my french. Even though they say that english will be language spoken in the center, dont bet on it. I cant imagine seeing the frenchies chatting away in english just because you are in the room.
Cost of living is high !! But, all in all skyguide is one of the better companies I have worked for.
Are you planned for GVA or ZRH?
Good luck anyway. See ya in Feb.