Vantaggi
You receive full military benefits including healthcare for you and your family as well as countless hours of support from multiple resources regarding any life situation you may find yourself in. The jobs are very rewarding. Of course, pick your job based on your preferences but if you ask someone in the CG which is the best job every individual will tell THEIRS! This speaks highly of the satisfaction of service members. Also, you DO get to pick your career path and rating (if coming in as enlisted). I have heard countless stories of people being forced or "tricked" into a job they didn't want in other services.
Svantaggi
The people I know of who do not enjoy their time in the CG are the people who really aren't built to live any kind of military life. It is definitely its own culture. Do your research on that front and be sure you are comfortable with what you are getting into. Either way, if you don't like it, you fulfill your obligations (4 years can fly by!), get a decent paycheck and free health care for awhile and meet some interesting people before getting out if you like.