I don't have access to the Windows version BUT you might be able to mitigate the small-font problem with some configuration. In the Mac version of Safari you can to to Preferences-Advanced and tell Safari to "Never use font sizes smaller than X." And in OSX's System Preferences you can go to "Appearance" and tell OSX to "Turn off text smoothing for font sizes X and smaller." Good luck!
Must say, that resizable textbox feature is sweetness! I've seen that done with JavaScript before, but built into the browser -- cool.
It seems to use its own font-smoothing algorithm rather than the Windows one. Everything (including tiny fonts) are aliased, which at least on my laptop is not as clear.