My ipad ate my earlier post.
For us, "maxing" out college savings meant buying the in-state prepaid tuition (VA) and setting up a 529 to cover expected R&B and book costs ($50-$60k). Then setting up a traditional savings account/vehicle for expected out of state costs (~$100k each). Our children are in HS now.
We haven't saved for the most expensive possibilities as we would hope that merit funding would put the actual costs closer to the expected out of state outlay (~$30-35k for tuition and fees). If they end up going to a more expensive school, we would either make them pay for the differential or pay for it out of current income (or a mix) - depending on the reasons why the school is their choice.
If they both end up going in state, we will consider helping some in grad school. Whatever their choice, they will be responsible for their own spending money. Eldest is gunning for Engineering at Va Tech and wants to be a co-op. One of our ideas is, if it goes as planned, he will be able to pay for R&B through is co-op. Then, we will would put that money (he would have needed) into a ROTH IRA for him. The dominoes have to fall just right for that to happen.