The RK-9000 current comes in 4 models with different Cherry switches (Red, Blue, Brown, and Black) to ensure your needs and/or preferences are meet. The RK-9000I will only come in two versions with either Cherry MX Blue switches (RK-9000I) or Cherry MX Brown switches (RK-9000BRI). These are the two most wanted Cherry switches for typing and gaming respectively. It also comes with both USB and PS/2 detachable cables.
There are no extra buttons, driver installations, key profiles, etc. This is about simply providing customers with keyboards that have high quality switches at an affordable price. Sometimes you just want to get a product that just works without all the extras you will rarely use anyway.