Pros
The only reason an intelligent engineer would work at Boeing is to work on their own projects. Since at Boeing it doesn't matter if you work or not, show up or not, care or not, or whether or not you are at all intelligent, there is no incentive whatsoever to do a good job. Hence, you can do whatever you want all day. The pros then are 100% life balance, and if you have a lot of outside interests this may be a good place for you.
Cons
If you want to do ANYTHING with your life, you won't do it at Boeing. Boeing is an archaic dump of a company that hopefully will get put out of its misery before the US taxpayers bail it out. Boeing is a big government company; you will only be promoted based on how long you have been there, not based on how smart you are or if you try or not. Everyone at Boeing sits around and chats all day; no one accomplishes anything. After a couple years at Boeing, you'll find yourself just riding out your career (even if you are in your 20s). Most people stay there 35 years and do 0 work. The union also makes it so no one can get fired, no matter how incompetent, and the hard working will never succeed.