Pros
Despite the current management and ownership group, Frontier employees support one another and generally have very good working relationships. If you can afford to work for an airline in Denver, CO, it's a great place to live!
Cons
Frontier was, at one time, a very proud company which provided exemplary service. Since its business strategy change to an ultra low cost carrier under private equity ownership, it has dumbed down the product (a la Spirit Airlines) and has replaced anyone connected to the "old" Frontier - the same people who made the company "Denver's hometown airline". While I generally understand the strategy change, it has been executed very poorly. The term "helter-skelter" comes to mind. If you want to see evidence of this, keep an eye on the branding ... there is none. I can tell you first-hand that employees have very little trust in management and are generally unhappy with the eroded culture.