It looks like PA does have a nice tax deduction. I LOVE Utah's plan. It is one of the few that has Dimensional Funds but it most cases it does not make up for a tax deduction. You would need to see how much the tax deduction benefits you.
You can change beneficiaries, so assuming you are not maxing them out you can use one 529 for all three and not having to worry about the tax deduction. You would have to go change beneficiaries each time the child needed the funds. It has gotten easier and can often be done online but can still be a pain.
The only other consideration is the investment choice. If you are using age-based plans it may be too conservative or too aggressive for different beneficiaries.
I also like for parents to consider their retirement first. Also retirement accounts, including the Roth do not count on FASFA, financial aid. I touch on this in my recent article:
I hope this helps!
Mark Struthers CFA, CFP®
This is for informational purposes only. Your specific situation would need to be taken into account. All information is subject to change. Not to be considered investment, tax, or legal advice.