i got mine after consulting with
these people after
posting this same question as you. he got me an offer where i now pay 20 EUR extra a month. i had consulted someone else prior to him and got the same quote so i felt it was a fair offer.
the guy, sebastian, is dutch and even met me once at the fischbrunnen to sign some papers.
EDIT: if you want extra hospital coverage, be prepared to pay with your eye-teeth (or out the nose and mouth). i looked into getting a 2-bed hospital room and that would have cost me an extra 30 EUR or so. i decided if and when i am again in the hospital, i'll just bring good earplugs and some potpourri and maybe my own separator. maybe for childbirth i'll tell my in-laws to fork out the dough for that