Sometimes the original product remains King of the Hill no matter how many variations on the theme its competitors bring to market.

So it is with the Prius. Toyota caught the public’s imagination in 1997 with the original sedan and immediately established a seemingly permanent connection between the Prius name and the hybrid genre.

How quickly ingrained that perception had become was soon apparent.

Advertisement - Continue Reading Below

In 2005, Honda came out with a hybrid Accord that tried to capture some of the hybrid buzz.The vehicle never sold well because the public had equated hybrid with economy and recognized Prius as the mpg champion. In contrast, the Accord was a performance vehicle that achieved very good mileage, but it did not offer Prius-like fuel economy.

So it remains as the evolved Prius hatchback continues its 15- year reign even asToyota and other manufacturers attempt to bring variations to market.

Indeed, Toyota has expanded the original lineup to include a Prius C (for city car), a plug-in, and the V. And even the original Prius now comes in five trim levels—numbered one through five. Our test car was a 2012 Prius Three. The Prius One is a fleet car, then the trim levels step up.

Our test car had a base price of $26,360, including destination and a bottom line of $26,732 with a mats/cargo net package and rear bumper protective applique.

The Prius remains all about economy, and ours was no different. It’s rated at 50 miles per gallon in combined driving (51 city/48 highway).We achieved 49.8 while not trying to maximize economy.

Additional strong selling points of the car include its rear-seat legroom and cargo-carrying capacity. We had house guests during the week, and the Prius was the vehicle of choice for local sightseeing trips and outings.

Mrs. G took her first look inside the Prius and said, “Wow. I really like this.” That was a bit surprising because it’s a nice-but-minimalist approach with fabric seats and lots of plastic on the touch points.

The center console angles up diagonally, merging with the center stack and leaving a big storage space underneath, similar to the setup used in Volvos.

The gauge package (available as a heads-up display on higher trim levels) is all digital and located in the center of the dashboard with all necessary information. Fortunately for me, the speed readout is large and easy to spot.

Power comes from Toyota’s proven Hybrid Synergy System. The combination of the 1.8-liter four-cylinder engine and electric motor produces 134 horsepower and 105 lb.-ft. of torque, a number that seems ridiculously low on paper but feels strong in operation. That power is transferred to the front wheels via a continuously variable transmission (CVT).

The driver has a choice of four power settings: EV (all electric), ECO, Normal, and Power.When you start the car, the default setting is Normal, which works well in most situations.

EV can take you up to a mile at under 25 mph with a fully charged battery. We had too heavy a foot and the engine kept kicking in long before that point. ECO mode works well in stop-and-go traffic and it’s worth pushing the power button for on ramps and dicey merging situations. We also called for that power on the hills of Rte. 1 inTopsfield and Ipswich with four adults aboard.

The hybrid components have an eight-year, 100,000-mile warranty. With more than a million Prii sold in the United States since 2000, those systems also have a proven reliability record.

Economy has increased over the years. The original Prius was rated at 41 mpg combined, the second-generation at 46, and now this third generation at 50.

On the road, the Prius was a fine sedan. The electric steering is ideal for average driving, but there’s lots of engine noise when you ask for extra power and road noise at highway speeds.The road noise likely is a weight reduction accommodation that helps achieve those hefty mpg ratings.

The Prius only weighs 3,000 pounds (actually 3,042) thanks to the use of aluminum (hood, rear hatch, and other components) and high-tensile-strength steel.

Styling continues to be an evolution of the original aerodynamic shape with increased use of LED lighting. The new Prius still looks much like the original. A friend who was following us on Rte. 128 said the taillights were extremely bright. LED headlights are available on the upper trim levels.

We had manual adjustments on the front seats and had no trouble finding a comfortable driving position. Moving up to a Prius 4 gives you power heated leather seating; a tech package on the 5 gives access to adaptive cruise control, lane departure warning, and heads up displays.

Our tester had the standard touchscreen system with Bluetooth and XM radio.We found it easy to stream Pandora radio through the system.

Recently, we’ve had the opportunity to drive two other versions of the Toyota hybrid system as it’s been used in the Camry hybrid and Lexus ES 300 hybrid. Both are considerably more refined than the Prius, but you pay about a 20 percent price in mpg reduction (to the 40 mpg level).

They’re great alternatives, but the Prius remains the best combination for the buyer for whom mpg is No. 1.