[gambiting]

Then why are we banning inefficient engines and impose huge tax on ones with large emissions? A car without a DPF costs less to buy and maintain than a one with it, yet no one makes the argument that "everyone should have access to cheap cars"?

Personally I would buy the car that has the most reliable and most powerful engine - even if it was a 6.0L V8 - but huge taxes on such thing are stopping me from buying it.

[grn]

I think that the problem of pollution, and other externalities, can be best handled by Pigovian taxes, not by explicit bans or heavy-handed regulation.