Bone In...Bone Out?
If you have the opportunity, always cook with the bone in the meat. It adds so much more flavor. Also, meat on the bone can be better value for money because you are not paying the butcher to spend time removing it.
The main advantage of cooking meat on the bone is that it adds more flavor and texture. The bone also conducts heat within the meat so that it cooks more evenly and prevents meat drying out and shrinking during the cooking process. Take a little care, when you use a meat thermometer, avoid touching the bone due to it's heat conductivity.