I just ordered the Baby Bob for my Hobie 16. Should I have purchased the Mama Bob? Or the next size up whichever Bob that is??????

You got the right one! I've used the Baby Bob on a H 17, and it was plenty to keep the boat from turtling. I think it's a great safety item, and a good choice! I took some ribbing from some friends for it, but have one to install on my current boat too. Brian