Our DS was in this situation until about 2-weeks ago. It took a lot of soul searching, research, candid discussions with mil contacts in both branches, two visits to WP (one overnight and one separate day visit), and an overnight visit to USNA. We are a retired career AF family, so kept our own opinions out of it and encouraged him to gather as much intel to aid in his decision. I read somewhere on this forum a comment that after all the soul searching, 'you'll be able to let one go easier than the other'. After our DS made his decision, we celebrated and then shared the news with family and friends. The next morning I asked him how he was feeling, if he had any lingering doubts, a pit in his stomach over whether he'd made the right decision, etc. He was able to solidly reply no. That was when we all knew for sure that he'd made the best decision for him. That was when we were able to share that we secretly were rooting for the branch choice he made. Notice that I didn't say the SA choice. The next 4-years are going to be a wonderful and turbulent 4-years of growth, but we feel that the following 5+ years should really weigh in the most when comparing your options.
I know that our DS became numb to hearing 'what a great predicament to be in' or 'either choice will be a good decision'. I really do believe what I read once-upon-a-time on this forum - best wishes as you weigh all sides and discover which one you're able to let go of easier, even if it's just a little bit.