@seattlecyclone, yes, my kids do go to public schools, so I see your point there. As far as investments go, I like what I've got the ESA invested in more than the 529, so that tips the balance the other way.
@avonlea, thanks for the links! The tax credits and deductions are on my list as ways to pay for college and are definitely a priority ahead of using the ESA or 529. In my case I can't claim them due to too much income, but that's a good problem to have.
And yes, I am super proud of him! He's starting off with a full-ride scholarship, a $1K / year stipend, 23-26 college credits from AP exams, and is pretty solid on his major. So he's got a good start...we'll see how he does...