In my 11 years in general EM, I never worked for a CMG. Even my 3 years in residency, was under a group run by docs. But unfortunately, CMGs have successfully crushed SDGs by outperforming them. They've run their businesses better and more efficiently. They do what hospitals hire them to do and they do it very well; that is to run the business of staffing EDs. And it should be no surprise, doctors in general, are much better clinicians than businessmen and that we've failed to outperform the CMGs. For the small minority of EPs that are good businessmen, my advice is to take advantage of the free standing option, as much as possible, where available. This is your best hope for independence, the greatest control of your practice environment and schedule. Where that's not possible or desirable, your best asset is to remain as mobile as possible. For the groups that treat docs the worst to survive, they depend on people being trapped by homeownership, and strong community ties. For employed docs to hold these groups' feet to the fire, you have to willing to dump them for low pay and poor job satisfaction, as they are to dump a doc for poor performance or refusing to tow the corporate line. Option 3, is to obtain a skill few other EPs have through a fellowship. That allows you to call your shots more, and have a range of options greater that the average pit doc.
But until you start to see the CMGs that treat the docs the worst collapsing into bankruptcy due to inability to staff EDs, they're going to keep doing what's profitable, and that is, to give you what you'll take, and treat you how you are willing to accept being treated. As long as docs stay landlocked, anchored by home and family in poor practice environments, the model will remain the same.