Pros
Good retirement benefits of about 15% pension + 401K match. Usually good life/work balance, you can take weekends off unless there is a pressing project deadline. Free gym onsite. Not as hectic as a bank. Politics are much easier to deal with than a bank. Management is flexible about outside responsibilities, appointments, etc.
Cons
Pay is lower than a bank. Expectations are high for job performance, and oftentimes unreasonable. Recognition for hard work is not really present. Management oftentimes gives in to front office demands without realistically assessing what it takes to meet those demands - in terms of man hours required to do the job correctly. Understaffed - employees are stretched far too thin. Market risk in Houston in the "model" risk group for BP, which means the workload and project demands are far higher than any other location.