Pros
Schlumberger is a great company to work for in regards to the training and gaining experience in the industry. The training to become a Wireline Field Engineer during PEPTEC-1 is first class and the opportunity to travel internationally is a given. Additionally you'll work within a team of engineers from around the world so a very good gender and cultural diversity.
Cons
Work-Life Balance. (This applies to Wireline) This has been mentioned in most reviews but I'm keen to reiterate this. You will only see friends or family once or twice a year if you work in Wireline. Be prepared for long days in the office (7am-11pm) and several weeks away at a time in the Field with only a few hours sleep over the course of several days. Additionally your contracted hours are a joke, if you're on a home country contract (I was on 35hours a week) you will certainly work over 85hours in the office, never have a weekend off and an extended period of time offshore with half the renumeration compared to the Internationally mobile engineers doing the exact same job. It all sounds negative, however if you're single (and celibate!), happy to only see your family & loved ones only once / twice a year and want to build up experience in the industry this is the job for you and you will be rewarded years down the line for your hard work.