After the $80k is spent for child 1 in the first two years, are you going to be able to pay $80k for child 1 while child 2 is also in school, and $80k for child 2 when child 1 graduates?
Instead it might be better to find a school where the net price after merit is $20-25k (529 balance over 4 years plus student loan of $5k per year)?