I can't in good conscious claim that a BYU undergrad degree is equivalant to a Stanford undergrad degree, even if you intend to go on to get a masters/PHD/JD etc. It is very possible to go to BYU and end up at the same place (same graduate program) as you would get to from Stanford, sure. But that doesn't make the degrees equivalant.
But there could still be reasons to go to BYU that are sufficient to overcome the imbalance of the degree. Finding a spouse and starting a family could do that, easily.
Fortunately, those are matters for young men and young women to work through on their knees and in their hearts. My opinion on the matter is pretty meaningless.