What can i expect from muay thai?

i want to start some sort of valuable self defense martial art. people say that muay thai is excellent, practical real world self defense, and fighting style. they also say that sometimes about kung fu. i also woud like an art that would encourage fitness. (i weigh about 200 pounds, 5'5), but i'm capable of running long distances and working out very hard, ( i just usually dont find the motivation). do you think muay thai is good for me? if so, what can i expect from a cl in muay thai? what questions should i ask? any terms used? how does muay thai compare with regular kickboxing? am i going to break my neck? seriously. i am considering this school nearby www.theblastma.com , what does it look like to you? thanks!