Real life flying (of all sorts) is very difficult to compare to sim flying. The physical sensations associated with real life flying have a very great impact on your ability to control the aircraft. However, in my opinion, the greatest difference lies in the improbabilities of real world physics. Air, weather, and aircraft are all instable and react to so many more factors than a computer flight simulation can... well... simulate.
Switchology, however, is a different matter. It is obvious that DCS:BS does an incredible job of copying the real life systems of the KA-50, but there's a lot more to start-up, even, than switches. Consider coordinating with ground crew, performing a proper pre-flight, or even just strapping yourself in! ;)