I would disagree that this is the most cost-effective approach. Sure, if you can afford it it's great, but the trainees you're picking up at MVP potential under $1m (<70 TSP at 21) are far worse of an investment than paying a similar price for a >50 TSP 18 yo PA/SS. Or better yet, a >60 TSP 19 yo.
Chances are you'll never reach cap of that MVP training the best-return (SF).