Requires API key. That requires a tutorial. But—not that hard.
You have to go to Google web fonts to see what you want, but it does provide a link. (And in a sense, why reinvent the wheel?)
Website provides pitch to premium version pretty fast—wish it would help you more to use the free version, before pitching the premium version. (You should help your users really get benefit from the free thing, and then the sale of the premium thing feels like a no-brainer, not a sales pitch.)
Provides support form, which is nice. But no support documentation, really.
Really, this is a very simple plugin. You still have to find another place to add the CSS rules to apply the fonts. Not a terrible thing, but would be nice if it were included.
But to its fault, it makes a separate Google Fonts call for each font. That is not as elegant.