20 years ago, I would always answer with - down a size. I liked the look and feel of a smallish frame.

Now, if I'm on the cusp, I'd go with the larger for handlebar height. I've realized that minimal standover is absolutely OK and - assuming you can get the reach right with at least an 80 or 90 mm stem - the larger frame will likely allow you to have the handlebars higher relative to the seat height. That's more important to me now than the look and sporty feel of the smallish frame.