A giant PITA but a tremendous asset for junior docs who are transitioning from the military into civilian positions of virtually any stripe.
My time as a division head was extremely valuable to my development as a physician. My emotional IQ developed by leaps and bounds, I learned how to be a better manager and motivator of people, a better resolver of conflict, and a better advocate for my department and its goals. It's also tremendously valuable from the business and regulatory perspective as worker bee junior physicians generally have little visibility of the business side of the hospital or the mountains of regulatory crap that come with CMS, TJC, CAP, FDA, and the rest of the alphabet soup of regulatory organizations that a hospital has to appease.
But understand that there is real risk in taking the position. I've seen some of my colleagues (who were stand up guys and gals) named in baseless harassment suits from angry civilian employees. I've been involved in appropriately disciplining subordinates who levied whistleblower complaints to regulatory agencies as a form of retaliation. Virtually all dealings with the union will drain measurable time from your lifespan. And remember, the culture of the military is to hang all those who recently touched the hot potato when a scandal breaks--if something goes down in your department and you are disliked for whatever reason by the hospital command, they may decide to hang you whatever your level of involvement in the issue. Remember that the first person to be relieved of command during the Walter Reed Scandal was MG Weightman, who, while the commander of Walter Reed at the time the scandal broke, had been on the job for all of a month and had nothing to do with the decisions that he was relieved for.
There is risk to your physicianship as well. The job really is a timesuck and will take away from clinical duties. It takes a strong and dedicated physician to not take the easy road of abdicating all clinical responsibilities to your colleagues so you can leave on time and have your weekends free. Good chiefs really do arrive earlier and stay later than their colleagues if they want to maintain their clinical skills and pitch in with the departmental workload. Furthermore, if you are a bad chief who ****s on his colleagues, it will come around to bite you in the end. The biggest douche of a chief I ever worked under can't get a civilian job in the city he wants to settle in because all the people he crapped on as chief who have joined the private groups in town won't hire him.
If you choose to do it, have some pride and do it well.