Pros
The pay and benefits are great and are the only reason to consider working here. However, if you look around, you'll find other companies offer similar if not better compensation and work-life balance.
Cons
A poor work-life balance, unprofessional senior management who often resort to swearing and threats towards others, corrupted management politics, nepotism, and a genuine lack of real leadership are just a few of the issues that contribute to Union Pacific's toxic culture. I've witnessed my management peers lie during investigations, blatantly falsify information, intimidate employees, cover up sexual harassment, retaliate against employees for reporting unsafe work conditions, and misreport injury and safety incident numbers to the company's senior leadership; all of which are against company policy and are likely illegal. Outside of the headquarters, most people are unhappy with the direction of the business but remain because they lack the education and skills to go somewhere better. Avoid at all costs; there are much better places to work.