Pros
There will always be steady work at this facility. Some units require more intense labor than others. You can easily raise a family with all the amenities you desire with employment there. Starting out, they'll contribute 5% of your gross income to your 401K (even if you don't put a dime in there). This is what they did to replace the traditional pension years ago... not bad.
Cons
Some units are very hard to bid out of, or in other words, be awarded an opportunity to move to another work group. Therefore; if one finds themselves in one of those units, they would have to leave the company in order to change their working environment. Some units have intense overtime requirements, where others are very mild with OT. Their 401K has great limitations regarding the type of funds that you can invest your money in... although, they do match 4% if you contribute 6%.