Just over a year ago, we purchased a Ford Fusion hybrid, that has same basic hybrid drivetrain as your C-max. We absolutely love it, glad to see you're happy with yours, too.
We got it mostly 'cause of how simple and easy it is to flat tow. Mileage was just an added bonus. I thought it was ridiculous that Ford got all that 'grief' about the mileage, so much so that they felt the need to compensate many owners for mileage not being represented right. My thoughts with it was, yea, mileage isn't quite what was advertised. I'm actually on average getting MORE mileage than was advertised! I average between 48 and 50 commuting to work and back every day.
Driving style, technique, etc. plays a huge role in the mileage you get with a hybrid. Even more so than with a conventional drivetrain. I think a lot of people got these things and drove them like a sports car, then griped and complained that they didnt get 47 mpg. If one doesn't insist on being the first one away from traffic lights and the last one to start braking....Well, you can easily get the advertised mileage of a hybrid. Otherwise, your mileage will be a little lower.
Not sure if you've learned this 'the hard way' yet or not, but one thing you do have to do when towing these Ford Hybrids: Run a charge line to the battery. There is a constant draw on the battery with them, and if you don't run a charge line, the battery will be dead after just an hour or two of towing. Very simple and easy to set up a charge line, though, and once you do, you'll never have to worry about running down the battery.