Whitman and I believe Wooster will give you a full financial aid guarantee before you apply (above and beyond their NPCs).
I also think the NPC cannot capture a variety of discretionary scholarships and programs that might be available. For instance, maybe there is a ton of merit aid but only for those who apply for and get in to the Honors College. Or a department/major that is selective and offers a 3+1 Bachelor/Masters program, so a student can get a second degree for “free.” Or scholarships available only to those who apply early.
That’s why I did not find the NPC a particularly useful tool.