If you are new to Combat Mission series, you probably don't actually want to start with CMBB. I did and it seemed rather overwhelming to me. I never played a truly realistic war game before that time and everything felt like chores. In CMBO, however, you can get a feel for what its like to strategize in WW2 and not have to be incredibly patient and already good at it to begin with. And overall, I enjoyed CMBO more.