Pros
I learned a lot being a part of the overall Koch organization (see Cons below). I had the opportunity to work in a fast-paced environment with exposure to many different businesses and international matters. Some people were very talented and great to work with (see my Cons below). Some business groups were top notch but this review focuses on the tax group so that is the reason for my overall rating.
Cons
The Tax group (Koch Companies Services) has some real leadership issues and practiced maybe (my opinion) two out of the 10 guiding principles. I believe the principles are good but they just were not practiced. The leadership (or perhaps better to say lack of leadership) created an atmosphere of distrust and unnecessary combativeness where you could see people visibly dreading coming to work knowing who they had to meet with. Talented people left and have continued to leave. Wichita is not a bad place to live but there are few other opportunities if your time at Koch does not work out.