I checked out the new Prius pages today and was disapointed that the fuel efficiency was significanly lower than the insight. (52/45 vs 61/70). I know that the insight is a smaller car, but even without the hybrid engine the metro gets (44/49) which is not that much worse. Does SULEV cut into the efficiency or is there something else going on?

I own a 2000 Camry and a 2001 Prius. The Prius has almost as much room inside as the Camry but the trunk is one cubic foot smaller. I haven't ridden in a Metro in a long time but when I did, it was a toy car. The Prius is a true family (4 adults plus child) car. The Prius, I believe, gets its mileage boost from a finely tuned engine running in a narrow speed band and the regeneration of power on speed reductions and braking. It is supposed to put about 30% of the braking power back into the battery. If an engine doesn't have to run at from idle to maximum, the tuning doesn't have to be as compromised over the entire speed range as the other cars. The Prius only idles to initially warm up the catalytic convertors. After reaching operating temperature as required by EPA there is no Prius idle. It shuts off. The motor starts it whenever it is needed.

With the exception of running the A/C.

Yes, the other cheaper cars like the toyota echo cost half as much and have comperable milage. If you really want good highway efficiency in a fuller size car, try a deisel (VW golf). If I understand correctly, the Insight requires lots of driver participation to achieve those high efficiency numbers as it has a manual transmission. I think the SULEV prius really shines in the city and in traffic jams. I think the SULEV concept is more to minimize pollution in dense traffic situations. I heard that in Korea cars are required to shut off their motors at stop lights. So it is more a question of where you pollute than the fact that SULEV cuts into fuel efficiency.

Weight. It is the weight of the car that makes the difference. I believe that if you had driven BOTH vehicle the difference between them would be obvious. I did not even consider the Insight because it felt unsafe to drive - I was seated too low, the car was very thin, and it weighed too little. Not to mention the noise in the INsight - Yuck. At least the Prius is a REAL car, and I am thrilled at the average 48-51 mpg we are getting.

I agree. I drove the Insight and it was a freaky little car that frightened me because of the lack of power. Merging on to a freeway was a "white knuckle moment". I have spoken to a fellow who owns one who said that it's really just a function of learning how to drive that particular car...and I tend to agree. After-all, one has to learn to drive the Prius in order to get the most out of it.<br><br>I would like to add that I just drove the Prius across Atlanta driving very fast (hey, it's Atlanta...and I was late...) and I still averaged almost 52 MPG. This car never fails to amaze me. I love it!