Compared to Priuses of early generations (2000-2009), the latest 2012 Prius provides a more responsive and more pleasant powertrain that still manages to get better fuel economy figures. The 1.8-liter four-cylinder engine is paired with Toyota's Hybrid Synergy Drive system, which uses an electric motor-generator to supplement the engine power and power the car solely on electricity at low speeds and under light loads. Total maximum output power is 134 horsepower, but at steady speeds on the highway, the engine is relaxed and the traveling experience is pleasant.
The 2012 Toyota Prius will keep up with fast-moving traffic if you run it hard, but you'll hear frequent howling as the engine runs up to its maximum speed and stays there. The handling is fairly good despite squealing from the low-rolling resistance tires on hard cornering. That kind of treatment, however, drops the gas mileage from the high 40s to the mid- to high 30s. Driving carefully, planning ahead, and using the "Eco" mode exclusively, on the other hand, will let any driver exceed 50 mph in city driving. There's also an "EV" mode that directs the car to power itself solely from the battery pack until it's exhausted after 1 mile or so.
Noise and vibration from the engine are well suppressed under most circumstances, except for the hot-rodding noted above. As with most Toyotas, the electric power steering is limp, lifeless, and utterly devoid of road feel--though it works fine and lets drivers hustle the car among competitive urban traffic. The four-wheel disc brakes work fine, when they're used for harder braking (regenerative braking to recharge the nickel-metal-hydride battery pack under the rear deck is the default). Pure acceleration times aren't swift, with 0-to-60-mph times of just under 10 seconds. But that's not really the point of the Prius. The whole hybrid driving experience is so different, with electronic control of virtually every aspect of the running gear, that you're much more likely to focus on increasing that fuel economy number than beating the adjacent car away from the stop light.