dude, the advantages of Muay Thai are....
....the training is very good for cardio vascular fitness and strength in abdominal and leg muscles, you learn RESPECT!!! if not then your teacher is crap or taking you for a ride. Its soaked in traditions if you get past the professional competitive form, as one or two of us here have argued before. Training in Muay Thai will improve your confidence by instilling a sense of indestructablness, toughness (which in my opinion must be proven in the ring) because of the nature of the training, I dont mean that Thai sparring is done heavy as often times it is not, infact most of the time fighters prefer to spar lightly, 50% or so.
The fact that you are physically pushing and pulling, kneeing and kicking during a pad workout, always being physically pushed to your limit by the trainer and spending some time, 20 minutes or so, each day working on your clinch technique prepares you for the intensity of a real fight, Muay Thai sparring is done carefully to prevent injuries as injuries can occur easily if you get too excited, sparring is taking a technique you have learned during a pad session and then after refining that technique on a heavy leather bag you then go into the ring to spar with a partner in order to learn how to apply that technique, some camps like to see how the heart of a new student is by pairing him off with someone and letting them go full power but only with the hands...
....many people have this notion that Thai sparring is done full power, it is not and dont think that because you do go full power you will learn anything other than not to go full power. I can almost garuantee that if you do enter into the world of Muay Thai you will probably ask yourself why you never entered sooner rather than later! Be sure to get a good trainer, a credible trainer. Also I personally recommend to learn the traditional side of Muay Thai, the origins of the sport, where it came from and dont try to get the info from the internet cos as I found out most ofthe sites are very misinforming.
this one is very good
http://www.muaythai.com
The disadvantages :
could be a developing of shin cancer but the chances of that are sorta like the chances of getting any other cancer I suppose. You can get a bad back, bone calis, split eyebrows, scars, broken toes, broken legs! Muay Thai is only usefull so long as you are physically strong as Muay Thai depends on strength as well as technique and of course there is the risk of death by internal bleeding and broken sternum, but if you dont compete that risk is considerably lower....
so there ya go, all I can say is go join a Muay Thai gym.