Public beta tests are common in the computer world where a group of fanatics pound your beta to death and help you find the problems. In the automotive world this activity is not only rare, it runs contrary to the cash spent on dressing future cars in swirly vinyl. The Prius plug-in is different. Toyota built 600 demonstrators and sent them to large corporations, Zipcar fleets and, of course the press. Even TTAC was allowed to drive one for a week. What does that have to do with the final product? And how does it stack up against the Volt, Plug-in Fusion and the 2013 Accord Plug-in? Let’s find out.