I just completed my McKinsey Solve Exam/game yesterday.
I don't know if my performance was good or bad. As I recall, I finished the first part in 19 minutes and I am sure that all animals will survive (though my food chain does not have an APEX predator in it cuz there was no need to).
As for the second part of the game, I had to defend a plant and they said that I should do 15 rounds per map though I did 27 rounds for the first map - 28 rounds for the second map - and 55 rounds for the final map.
Is this considered a good performance?