Pros
You do basically nothing at work. I can show up from 9:30AM and leave at 4:00PM and nobody bats an eye - until a problem comes up and then I get my hand slapped but nothing actually happens. GM is also known as Generous Motors because they overpay workers for doing low quality work.
Cons
Corporate toxicity at its finest. In Detroit, the international operations, it's all about brown nosing, fake laughter, and speaking Spanish to one another. Management is completely incompetent and not looking to change or learn anything. They don't want to disrupt their cushy lifestyle of sitting back and doing absolutely nothing. Employee turnover is high - because, chances are, if you are anywhere near competent or talented, you will realize this place stifles growth and settles for mediocrity.