Performance based Hybrids would work very well for police/emergency cars in the States. The fact that they do sit idle for long periods of time would save a lot of gas. But one problem hybrids have right now is, if you put the car in park, the engine starts back up and stays on. GM needs to work on a way to have the engine cut off during long idle times...

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1987 Chevy Spectrum - 200,000+ Miles -Junk Yard
1994 Honda Civic DX Coupe - Truck Hit it
1998 Acura 2.3 CL - End of Lease
2002 Acura TL 3.2 - End of Lease
2004 Acura MDX - End of Lease
2007 Mercedes ML350 -Lemon
2007 Honda Civic Hybrid w/Navi - Active