I'm at an SAE school right now, not the one you're talking about. I already had a lot of basic knowledge, one of the people who just knew a lot, but didn't (doesn't) have the practical experience. The things I learned in class haven't been so much of a help for me. But the practical time in the studio's is very cool, and the school is great fun. I'm having a very good time there.
However, my impression from the school: The people are great, and everybody wants to learn, but there are just very little people who (can) really teach you practical things.
Compared to (my impression of) a internship: at school I get a lot of theory, and I can go my own way in the practical time. At an internship, you will get little theory, but will get fully guided in the practical side of recording and mixing, by people who know what to do so well that they can earn a living with it. However, the time to experiment and try out things will be very limited, of course, depending on the time you've been an intern, and where you are interned.
"Music is a treasure hunt. You dig and dig and sometimes you find something." - Ry Cooder (Buena Vista Social Club)