Are you asking what should you choose as what would be better for medical school? If that is the case that is the wrong question. The question is what would you prefer to do? If you want to go into public health eventually and not be a wet bench researcher, and eventually deal somehow with policy, then the Senate internship will seem to be better. But they should be based on what you want and not what you perceive is going to be somehow better to get it to medical school