Hello people,
So, I bought CC2 and CC3, and will start with 2 soon, but I wonder, having seen that there is a speed option, what speed would you advice to play it?
This, I mean in term of realism, not of difficulty.

In CC2, Fast is close to real time. Personally, I tend to play on Medium most of the time and occasionally resort to Slow. Playing the game on Fast will likely not give you time to issue/reissue orders quickly enough to account for changing events.

Fast for CC3 and Medium for CC2.