The more I think about diesel, the more I want a petrol. I'm currently doing my best with my old diesel, but the 10000 French dying every year because particles isn't worth the small saving I have compared to a small petrol (and I drive 22222km/year = 13800mi/year). See
Green Vehicle Guide | US EPA and use the "Look Up Greenest Vehicles" menu for California state to see the cleanest diesel are only at ULEV while a RX450h is at SULEV.
Also I wouldn't risk to make a kill switch on a modern diesel (with high pressure pump).
I also looked at C1/107 and smart for2. I don't really like the twingo and it looks like a toy to my wife's eyes. Sadly any option makes the price to rise very fast, the rpm per example, and lots of options aren't available, cruise control per example (which is a must for me as I want to make A-B-A tests). With all these small cars you have to buy a SGII.
Prius and Insight are at
SULEV level since so long...
unbreakable and certainly much more fun than small cars.
Both Prius and Insight have great Euro'ncap notation.
A good point for the Prius : it has a plug'in kit available, perfect for small daily commutes
Even if I have a long daily commute, this makes a second hand Prius my best wish.
Denis.