Pros
Great company, one of a few good paying employers in an area that does not have very many large employers who pay well. The 9/80 work schedule offers flexibility and the people are generally very friendly and cooperative. The work is interesting and unique and the big-quality, defense-related work BWXT is involved with is a great source of pride for all workers. The company split when it spun off its fossil fuel division (Babcock & Wilcox), the remaining company resurrected the former BWXT name for its primarily defense and nuclear related business. The split has been very well received by employees.
Cons
No real down-sides or cons. BWXT froze the defined-benefit pension plan last year (2015), which was a downer, but it is not unique in that almost all private employers did the same years ago. I'm surprised they left it as long as they did, frankly. We still get a 401k, with a match and with extra $ added, based on years of service, something very few companies offer.