Yeah, 529 has tax benefits but the way I see it, those benefits only exist IF you were planning on utilizing that money for college. You wouldn't spend extra money on business expenses just to deduct from taxes. Same principle here. UTMA is a stop-gap anyway, just until their old enough to be on payroll and contribute to a Roth IRA (where earnings can be spent on educational expenses without being taxed).
In state tuition for Ohio Sate is 29k but spend $5k on super expensive ACT tutoring, your kid gets a 36 on the ACT, and now Ohio State's tuition is negative 5k (make your kid give it back to you for the ACT tutoring). Or score high on the PSAT and get national merit. I lost count of how many full ride offers I got because of national merit. Much more financial sense to spend a few thousand on test prep (honestly, hundreds is more than enough if they've got a solid foundation) in 10th grade rather than 30k a year after they graduate.
In short, if someone's doing well enough to be considering tier 2 (tier 1? basically the schools right below H/Y/P/S/MIT) private schools, they're doing well enough to get sizable merit scholarships at various public universities.
