I'm sure there is plenty of data on this, but if you are looking at Harvard, Princeton, Yale, etc., they are still gateways to an elite path. In ways that BYU is *occasionally* for some students, but not nearly as often as these schools.

And I have read here on CB that the LDS communities at theses ultra-elite universities can be really tight-nit. So, it can work.

All that said, I am a huge proponent of THE BYU for undergrad. I would only consider Ivy if either (1) someone else was paying for it or (2) I had so much money that the opportunity cost of paying for it was indiscernable.