We did have an ex-JNB chappy here, but he has moved on to even greener pastures.
Bear in mind, that skyguide employs about 25-30% foreign controllers from all over the world. Needless to say that you will find a few guys who are against foreigners, but it is the exception.
You will pay tax at source and depending on your salary scale, you should take home around Sfr9000/month.
Training is about 4 months before you get checked out. Then you'll go back to the sim and do it all over again for TWR. As an APP controller you have to be fluent in German as all the cocordination with the vehicles and tugs is in German. But if you do a few language courses you'll pick it up quickly...
If you want to live in another canton, you must just tell skyguide beforehand and they'll arange the work permit for you.
I'll try and get one of the app guys here to give you more info. I'm not too sure about the training and such, but hopefully he can help you further.