Pros
I worked in IT for Genesis; I started as a contractor and then converted to full time. Every single person I met at Genesis was kind and helpful, from the front desk to fellow IT people, from HR to the CEO himself. I learned a lot at Genesis due to the demands of complexity and security in finance and had excellent support from my immediate manager and senior co-workers. I gained a lot of very valuable experience. Midway through my time there they hired back an excellent CTO with great leadership skills, which turned the IT department around in a big way. My primary reason for leaving was that I needed to work somewhere closer, not because Genesis treated me poorly in any way.
Cons
There are two main downsides to Genesis in my view. First, the nature of the industry. There are no two ways about it, they do credit and loans, particularly retail cards like at furniture stores or jewelers. Because of this, a large part of the business involves collections, and the end goal of the company is to both loan and collect more money. I didn't find any of Genesis' practices predatory in any direct way, and they emphasize integrity in their corporate culture, but at the end of the day, you are working for a company in the secondary market credit industry. I did not enjoy this and had a hard time rationalizing my involvement in it. Secondly, you are working with massive amounts of legacy code and legacy technologies. Financial data is vast, complicated, and must be secure at all times, so it makes sense that tech must move slowly, but it can be less than exciting when opportunities abound in this city to work with bleeding edge tech. We tried to implement new tech where we could (mostly when a new feature or program needed to be added), but the sheer volume of work on the legacy code means you are spending most of your time in older systems.