Ventajas
Good medical insurance plan. Makes sense for a huge company. I took work home occasionally, but I did that for myself. There was never pressure to work outside the 40-hour work week, so that's a pro for people with families.
Desventajas
Maybe the experiences are different when you were hired by the company proper and not absorbed as part of a company that got purchased by them, but I never got the feeling upper management cared about us. It's hard to keep personal morale up with that kind of environment. I thought it was silly that our internal upper management was forced to jump through all the hoops of LM's annual review process, when it was never made clear by any management - ours or LM's - how we could work better, individually or as a team, to increase productivity and be promoted and/or get raises. Not sure if this only applied to us "stepchildren" but I was a team leader and was required to provide feedback on my team members' work. One of our lower management bosses that was handling annual reviews for those staff said she had to change my ratings because there was a specific # of people who could be ranked at the highest level of merit and therefore those who weren't at that level weren't eligible for the best raises. While I realize that's standard in corporate, I did not anticipate this and got out there as soon as I could.