drop bear
Sr. Grandmaster
The wrist and hand don't generate any significant amount of power for a punch, so immensely strong wrists won't dramatically increase the power of any punch (though they might allow you to use more power from the core of the body, safely).
As for the simulator, how much does it cost, and what are you expecting the value to be for yourself?
You are only as strong as your weakest link. So if your core is good but your wrist gives out then the core isn't able to do its job.