Pros
Union has a strong training and onboarding program to prepare new employees for working in a bank environment. They offer reasonably strong benefits. Depending on where you work, you may end up with a really wonderful team - there are some truly good people working there. It can be fulfilling work because you often feel like you're making some positive difference in people's lives, no matter how small.
Cons
The compensation is laughably poor. High performers do not stick around because they are not given any incentive to do so. The bonus program is unachievable unless you are lucky enough to be in one of the busiest branches. Compensation is also uneven, leading to dissatisfaction amongst longtime employees. It is almost unheard of to become a branch manager from inside the company, as they are only interested in hiring managers from other banks who can bring in new business. There is a profound disconnect between what is expected by upper management and what is actually achievable in a live bank environment. This all too often leads to a lack of concern for and attention to new policies as they are handed down, and inconsistent implementation of existing policies. Management has unrealistic expectations of the productivity of branch employees, leading to overwork and burnout.