Pros
You will get to work with some pretty amazing coworkers, that make the job bearable. While a lot of customers can be a pain in the butt, you will meet some customers that never fail to put a smile on your face. The hours are flexible, and it's pretty easy road to get more hours, and to request for days off. For the most part, they will honor your availabilities.
Cons
Working at McDonalds is kinda like being in an abusive relationship, you stay because you love the people you work with, and because you want/need to get paid. However, when times get hard, and when you don't perform to their godly levels of expectation. They will treat you like trash and dirt, and you will get crap on for the stupidest, and for the silliest of reasons. It's a thankless job with little reward, and there will be days when the managers treat you like crap just because they've had a bad day. One day you are their punching bag, and the next day they can be your very best friend. It's ridiculous and downright crazy.