Well, I have only done an internship in Field Engineering in Schlumberger and not experienced work as an engineer till today. As per my internship observation life as a feild engineering is very challenging and dyanmic. One needs to be both physically and mentally alert all the time to be able to accomplish filed operations. Its a perfect blend of techno-mangement profile where your expected to perform well-site operations using your technical knoweledge and manage the crew, client and the entire job.