The 5-speed Insight creates the least amount of greenhouse gases of any gas vehicle on today's market. Credit the lean burn. The 5-speed Insight also produces a high amount of NO2 - blame the lean burn. For this reason, California either does not give the 5-speed Insight a hybrid credit, sell it or both. Last year on a trip to northern California, I saw Prius', hybrid Civics, but no Insights.
The Insight CVT does not have lean burn, so it does not have the NO2 rap. It also has FE no better than the Prius or 2006 HCH. It does generate more greenhouse gases than the 5-speed....