All those figures are an improvement over the Prius, despite it being the more slippery of the two with a drag coefficient of 0.25 versus the Auris Hybrid's 0.28. With CO2 emissions of between 89 and 93g/km, depending on wheel size, car tax isn't a problem because you won't have to pay any. The same goes for the Congestion Charge for those living in or near the Smoke.
The EV button allows for electric-only motoring
As with the Prius, when you hit the Start button nothing happens beyond the dash lighting up like a Christmas tree, because the Auris moves away under battery power with the engine only joining the fray when required. Press the EV button and you can travel in leccy-only mode for around one and three-quarter miles at speeds of up to 30-odd mph, which is handy in slow moving traffic jams or trying to run down chronically inattentive pedestrians.
Cabin architecture is somewhat basic
Being rather smaller than the Prius, there is a touch less space in the cabin, but five adults can still sit comfortably, as long as those in the back are not too long in the leg. Luggage is more of an issue because the boot floor, replete with 'Hybrid Battery Pack' sign, is high. To be fair, the battery pack only steals space from the under floor cubby – poor boot space is a feature of the entire Auris range.
The boot accommodates the battery pack and is bit on the high side
Once inside, the Auris is not a noticeably less pleasant place to sit than the Prius, despite the basic cabin architecture and fittings being those of a fifteen grand compact hatchback, rather than a twenty grand California eco-cruiser.
Fuel Consumption = Emissions
The problem with the Pious was always that Toyota wildly exaggerated it's fuel mileage figures. IIRC they were quoting something of the order of 60+mpg on the combined cycle, but every owner I've ever heard from tells me that were getting about 66% of the quoted figures.
40+mph might be pretty good for a car of that physical size, but it isn't as good as most competing diesels. If you're one of those people who think that CO2 is the only emission you need to worry about (and most Pious owners I've spoken to fit into that camp) then you can pretty much categorically state that the Pious is emitting more CO2 per mile than a diesel of similar size.
Now most people find that they don't get the quoted mpg for their car and to be fair to the manufacturers it's not their fault. The tests are unrealistic and don't replicate real driving conditions. As a result of this most people get a few less miles per gallon than the official figures would lead them to expect. I've known a few people complain to Toyota about their fuel consumption and they've all been told the same thing, that they're not using the car as it was intended. But hold on a minute Mr. Toyota, every car is supposed to go through the same test and most people get something close to the figure produced by the test. They don't drive differently in the Pious than they do in any other car. How come the Pious can't do it? The only thing I can think of is that the car was very specifically set up to do well in the tests rather than in the real world.
This is the main reason that the nay sayers deride the Pious. It's quite good, but not nearly as good as it claims to be.
The main reason people deride celebrity Pious owners is that while they own a Pious they also tend to own a fleet of huge gas guzzlers too. Owning one Pious does not somehow absolve you of blame for the damage done by your Camaro, 599 and Range Rover. It's pretty much the same way these celebrities tell us we shouldn't fly on holiday because it's bad for the environment, but charter a private jet to get to Cannes.
My Toyota iQ does over 60mpg, seats 4 and costs £10,000.
Why would I spend and extra £10,000 to get an extra 2 or 3 mpg? In order for the slightly better fuel economy to pay me back (forgetting the higher insurance - the iQ is group 2) I would have to run it at my 6,000 miles per year for a total of 366 years!
The iQ is a normal petrol-engined car, and also attracts 0 road tax due to the 99g carbon emissions.
It would be interesting* to know
How far you have to drive in order to recoup the extra purchase price compared to a standard car. Back of an envelope suggests that if you travel a fairly typical 12,000 miles a year, then 60mpg against 40mpg** will save you 100 gallons or around £500 at current UK prices. So if it costs an extra £5,000 you'll take 10 years to get your money back. (In the US where petrol is less than half the price, it will take much longer.) A fuller analysis would take into account maintenance costs and taxation, but I don't think it would make an order of magnitude difference.
* for suitably low values of 'interesting'
** ignoring the fact that you can get a standard diesel that should give you 60mpg - but even my 2 litre turbo gives me better than 40mpg on long journeys