I surely would go in for Lexus GS 450h The New Hybrid car, which is a 6 cyl 3.5 HEV ( Hybrid Electric Vehicle) ,attains a fuel eficency of at least 28Mpg in city conditions (even as bad as Indian ).
Now The answer to why I would go for this is because , first they are pollution free, second they save scarce fuel.
Hybrid-electric vehicles (HEVs) combine the benefits of gasoline engines and electric motors and can be configured to obtain different objectives, such as improved fuel economy, increased power, or additional auxiliary power for electronic devices and power tools.In crude terms we can say it runs on Gasoline and and built in generator produces Electricity which helps in running the car, the car switches over from gasoline to Electric current as per need of the drive.