Pros
Compensation is generally competitive with a salary + bonus structure that applies to even lower pay grades. At higher pay grades, the bonus structure ramps up and can become significant. Option to work alternative work schedules such 80 hours over 9 days is a big bonus. People are generally of a very high competence level.
Kontras
Review process for salary and bonus determination has become a bit of a joke in recent years - expect something pretty arbitrary. Opportunities for advancement in non-HQ locations are extremely limited. Downstream is the red-headed stepchild in relation to its big brother Upstream. When Chevron talks about using technology as a competitive advantage they mean in Upstream - Downstreamers can expect to claw mightily for resources with little likelihood of success.