This is much like the "best" chain lube posts

It really depends.
Different classes have different goals (and not just ending up with a functional frame). Different instructors have different styles, some more hands on, some more foundational understanding focused, some classes have fewer students then others. Some are located in places with much else to offer (Portland) then others (Niles MI), but this also speaks to distractions.
I would do some homework about the nature of various schools and how one learns/interacts. Andy.