I also say to export at 300 dpi. It changes the 'size' but does not chg the height, width size. It adds the extra pixels, which will give you better resolution. Do a few tests to see what I mean. Export one at the 96 size, then one only changing the dpi box to 300, open them both next to each other and compare. Should be the same size, meaning same height, same width, just a better, sharper view. The size thing can be confusing, there's size, then there's size, lol. Wish they'd put diff words in the 'size' that shows on the png export.