Pros
Our company was acquired by Altamira last year, and they went to great lengths to make the transition as smooth and welcoming as possible. There's a very upbeat culture and relaxed but professional work environment. The mission is #1, but they know it takes good people to accomplish that mission, so they do whatever they can to keep employees happy. Good pay and benefits. Allowances for training and broadening of skills. Free snacks in the break room. There is a small company feel but big enough to provide for extra resources and opportunities for growth. Everyone is valued for their contributions. This is the kind of company you could grow with for a long time.
Cons
The only downside I can think of is the employees are distributed among different sites, supporting different customers, so it could lead to some isolation. But this is mitigated by numerous (at least quarterly) corporate get-togethers and fun outings (eg, family picnics, minor league baseball games) to help build camaraderie and corporate identity. So it's all good.