re: Is trying to hit $0 refund or payment in April worth it?

I just try to get reasonably close. It's true that a refund amounts to an interest-free loan but but the amount saved isn't much unless you are Donald Trump.

For me personally, there's also the fact that Virginia income taxes are pretty low so that is what I actually try to target. I usually get a refund from VA but owe the IRS money.