Vantaggi
The only pro I can think of is 'working at a big company'.
Svantaggi
This is the worst choice of employer you could make, especially over the coming decades where oil & gas industry profits are expected to continue going downwards, or at the best stay where they are. Schlumberger is aggressive when it comes to layoffs in the face of downturn in the industry, and in the coming years these layoff cycles will get closer and closer. The only competitive advantage SLB provides to its shareholders as compared to the competitors is the massive 'cost cuts' which basically meant laying off many talented hard working employees over the past three years. The demand for the products and services they provide is not increasing in any way in the long run. It goes without saying that this is definitely not an ideal company for millenials and later generations.