Pros
The two best things about Harris is their commitment to their core principles and the vast resources they offer all employees. With respect to their core principles, I'm particularly impressed by their respect for the individual. I feel I've always worked at great places -- but Harris excels in caring about their employees, respecting them as individuals and also in helping them to grow and develop, and in supporting them in their private interests as well as in their career.
Cons
There aren't many cons. You'd think their size would be one. But it's not. Their size provides an endless wealth of resources for information, advice, mentorship, and learning -- and opportunity to explore different jobs, different people. One con might be rather tight restrictions on pay raises. Standard raises are barely standard of living, even when a business unit excels. But they are always fair, and do pay close attention to salary correction where needed, as well as offering opportunities for spot merit raises for high performers.