Get her hand measurements and chat up rider's discount or stt. They're good about doing the research for you and will give you some recommendations. If you're nice, they might even offer free returns /exchanges if their suggestions don't fit right.
i wouldn't worry too much about the break in, just if it has any existing issues and if they did the service. that said, use that pricing as leverage against a local dealer, i'm sure someone will play ball. good luck, those are cool bikes!
how can you like the c5 but not the c6? they're basically identical looking other than headlights... well, except the c6 is more awesome. like, in every way.