I have one of their boxes installed. It seems to provide a clear picture of overall performance with a monthly report. I'm doing this because I'd like to think it helps the FCC keep the ISPs honest.
PS - Card carrying Libertarian. No the FCC isn't spying on me, and yes regulation of ISPs is appropriate. If we've broken the free market by granting a local monopoly or limited oligopoly then heavy regulation is appropriate. Consumer choice is better, but this is the best we can do with what we have today.