So I ended up validating 9 classes going in as a plebe (I came directly from high school).
I am still conflicted myself as to whether this was the right decision for me. I struggled somewhat plebe year because I hadn't had to deal with very much stress in my life and didn't really know how. My academics suffered, not because I didn't get the material, but because I was too caught up in other things. I was taking essentially all 2nd semester plebe or youngster year classes during my first semester. Sometimes I think if I had retaken calc and english and chemistry and government, then I wouldn't have done as bad because I would have had to put less effort than usual as I would have known much of the material already.
After plebe year, my CQPR markedly improved as I figured out how the Academy works, and I could get back to focusing on school. I did significantly better with the more advanced material after plebe year, just as some of my classmates dropped significantly in performance after they left the structure and familiarity of plebe classes.
Now as a rising firstie, I am experiencing the benefit of my validations. After first semester youngster year, I haven't and will not have more than 17 credits in a semester. I have so much room in my schedule that I actually started the Computer science syllabus in addition to my main major (OR). I could have easily gone abroad for a semester or had room for VGEP. If I were at a civilian school I probably could have front loaded and graduated a year early.
My plebe year affects my OOM to this day, and that sucks because I could probably be a couple hundred spots higher than I am. But I have never had to overload and have had the ability to take pretty much any extra class that I want because of the free space in my schedule.