Same as Deb for me - we are both going through the sams hospital and I'm doing Shared Care too.
The major reason for me is consistency and convenience. The hospital tends to say your appt is at this time, and you can't change it. hard when I work as an engineer to say - I know its 10am, but I'll be back in anywhere from 30mins to 2 hours depending on the outpatients clinic!
So I can get 5pm appts with my dr, who is lovely, adn Shane and I can fit in a time that suits both of us.
Money wise - I have only had to pay for one blood test for Downs Syndrome, but apparently some of that is rebatable through Medicare. I pay the the full amt with dr, and then get refunded $27 (??) through Medicare. For $13 a month, the convenience is worth it!
I dont believe there will be any costs through hospital, although antenatal classes are $60 for 5.
Hope that helps,
Fiona