this
surviving in Fox3 environment: 1) will bring more satisfaction 2) will bring knowledge on how Fox3 trucks operate 3) will make you develop more sophisticated tactics 4) will boost your situational awareness to the level, which you would never reach in Fox1 environment (and mainly - make you understand it's not the missiles or aircraft that win the fight, but situational awareness and the pilot)
currently in DCS Mirage 2000C is simply the king of Fox1 environment - you don't have to be a good pilot in order to win
red Fox1s are broken, blue Fox1s are slow
in this scenario you can kill pretty much anything in the Mirage head on, not developing any sophisticated strategies and tactics