My 7 year old already talks about replacing his arm with a bionic arm. We will mesh with machines in the next 25-30 years...
I have no issue with artificial joints. Artificial organs like hearts, pancreas, etc, will save lives.
Trying to actually improve people and alter them, though, crosses a line we need to seriously debate. Like genetic engineering for improvement as compared to repairing defective cystic fibrosis genes, it is both an ethical quandary and risky.
After all, liberals are saying that reading to your children disadvantages them compared to parents who are too lazy to engage the kids. And now you want to boost the abilities of someone with an upgrade, and the option to genetically engineering the next generation to be even better?