This car has a poor suspension, and doesn't feel nimble or pleasant to drive. The older model (called Echo in North America, the equivalent of the first generation Yaris in the rest of the world) had more pleasant handling.
Tall drivers over 6ft (1.80m) don't have enough leg room. The front seats are fine for city trips, but uncomfortable for long drives outside the city. As a comparison, I was very comfortable in the old Echo for long trips.
The car is very spacious inside, and pleasant to the eye. Visibility is good, city parking is very easy, side mirrors are large, and the seats are high and easy to access with a high seating position, a little similar to that on the minivans.
The car is very stable on the highway despite the short dimensions. Noise is kept to a reasonable level. Better than the older model. Emergency handling at higher speeds is good and safe. The car handles well in snow when equipped with quality winter tires.
The dash of the car (the portion between the steering wheel and the windshield) is made of a special plastic that reflects the heat. In summer sunshine it doesn't get hot, which is a plus for cooling the interior of the car.
The car has proven reliable (no major mechanical issues) and the engine components appear to be of good quality and well put together.
This car has not received good crash test marks. In fact, in the regular crash tests it did well, but when crashed against a larger vehicle (against a Toyota Camry), the Toyota Yaris suffered serious cabin deformation (search "Yaris vs Camry" on YouTube).