I own a 2016 Mazda 2, or Scion/Toyota iA/Yaris sedan as it is called in the US. It has better interior than the Fit (Jazz), Versa, Fiesta, and Yaris hatchbacks. Equipment-wise it's on par with its competitors, although I've heard that in some markets, the 2 doesn't come with features like auto-leveling headlamps and cruise control.
Fuel economy is good, I regularly get 35 MPG in the city and I managed to hit 62 MPG on the highway.
Now, the bad:
Bigger exterior dimension than the Fit, but has probably the worst interior space in the segment. Trunk space is pitiful, even for subcompact standards.
i-Stop system is finicky, it has to meet 3 requirements for it to trigger: AC, battery, and engine. If you set the AC to roughly 4C lower than the ambient temperature, you will never engage the i-Stop system because the engine needs to run the alternator to power it. Tiny movements of the steering wheel will restart your engine, so will a change in brake pedal pressure. You can shift to N and let go of the brakes. If you touch the brakes again, the engine will start. Be prepared to change the battery and starter motor if you engage it often. Crawling traffic is HARD on this system, so just disable it and engage it on traffic lights.
Auto-braking system (SCBS) will probably cause an accident in busy urban traffic, especially if you have plenty of overtakings or lanesplitters. Example: I drove all the way to Vietnam and the SCBS triggered every 10 seconds because of scooters cutting in. I got rear ended more than 5 times because of the sudden braking.
Questionable QC on the rear bushings and general suspension/power steering system. Early models (pre-2013-2015) has problems with leaky power steering and cracked control arms/bushings.
Overall, it's a great car, with small but annoying faults. It's not as fun to drive as the Jazz, for sure, but it makes up for it in its interior and fuel efficiency.