Times:

10 simulations: 0m0.032s
100 simulations: 0m0.031s
1000 simulations: 0m0.037s
10000 simulations: 0m0.124s
100000 simulations: 0m0.815s
1000000 simulations: 0m8.345s

Questions:

Which predictions, if any, proved incorrect as you increased the number of simulations?:

With a small number of simulations England's prediction proved incorrect.

Suppose you're charged a fee for each second of compute time your program uses.
After how many simulations would you call the predictions "good enough"?:

It seems like the predictions stabilized after about 10000 simulations.