Pros
Great benefits, including insurance, pension, high match on 401(k), matching charitable donations. Salary lower than competitors but total package is competitive. Wide array of job and career options, especially for those with chemical engineering backgrounds (arguably the core discipline especially in the downstream side of the business). More freedom than some of its competitors who centrally dictate many of the decisions. Largely self-directed career planning.
Cons
Oftentimes the centrally run initiatives and programs lack foresight and effectiveness. Managers often speak of simplification but very few of them will stand up to their superiors when push comes to shove and push back against senseless work. While it can be great as an engineer to have ample opportunities at all levels of management, engineers aren't always the most charismatic leaders and the culture reflects that.