We chose this theme for the PAC at my sons' school - being a volunteer-run organization, we are very cost-conscious. I was hesitant, because I'd had experiences in the past with free themes and been poorly disappointed, frustrated and exasperated.
Like any theme, it took me an evening to "get to know," and now, Tempera has proven to be flexible and easy to customize. Even for the appearance hacks I needed to make, the code seems clean and easy to navigate for this non-coder. There are a few hiccups I've had, with standard things on our site not appearing like they do in the demo (the sticky post on the presentation page), and with plugins not playing nice (Recent Facebook Posts by Danny van Kooten, and The Events Calendar by Modern Tribe - two plugins I've had work just find on other client sites), but overall, very very happy with our choice to use Tempera!