Pros
friendly co-workers, small town environment (but close to the city) with great facilities - they spent a bundle and it shows! Cargill definitely believes in its products, believes in its people and generally makes you believe as an employee that your input is valued and you are valuable to the company.
Cons
Depending on your role in the company, geographic location can become a career limiter. With international HQ based just outside of Minneapolis, if you want to advance in the company, be prepared to move there. Also with being such a huge company (when I was there they were the largest privately held company in the world), sometimes a unilateral decision would be made at HQ that just didn't make sense to the field offices. But as long as the business unit is making money, the guys at the top didn't mess with it too much.