I bought one of the first of the SkyActiv Mazda 6 sedans, and have been very pleased overall. It suits me well, but a few aspects probably limit its appeal.
Like other cars in the so-called medium class, it is very much a family-sized car in the cabin. The front accommodation is spacious enough, and there is plenty of legroom in the back, without being up to limo standard. The sunroof (in GT and Atenza variants) does limit headroom. I can use the driver's seat without difficulty by using the height adjustment, but the passenger seat is fixed height has me needing to wind the backrest back more than I would like. The boot capacity of 420 litres is low by the standards of its competitors, despite the use of a space saver spare. Later build vehicles addressed this criticism by making the spare even skinnier.
Despite the size of the car, there is a distinct cockpit feel from the driver's seat, with the high window line and all controls close to hand. Even the rear vision mirror is very close (at least to my sitting position), so it blocks some view of vehicles coming from the left if they are coming down a hill.
I get 7 to 7.5 L/100 km in average driving - generally commuting from outer to inner suburbs. That includes sometimes making the most of the diesel's torque for its very impressive but quiet standing start acceleration - after the briefest of lag periods. Top end power for overtaking is adequate, but clearly short of what I had been used to in past six cylinder petrol cars. Turbo lag is more of an issue when I am gently cruising at 60 km/h and about 1500 r.p.m. and want to move to a faster-flowing lane. It's better if I can anticipate a bit and change down first, using the small paddles.
The Atenza comes with the maximum available safety equipment. The lane departure warning might one day save my life, so I leave it on, even though it gives false alarms on narrow roads. The swivelling headlights work well, but aren't as bright as I'd like. The auto high beam generally does a good job, but occasionally fails to dip when following another vehicle, so I have to take over. The blind spot monitoring and rear cross traffic alerts both work superbly.
The idle-stop system works smoothly. It is very easy to get the engine to restart by easing pressure on the brake pedal in anticipation of the lights changing. There is, though, too much delay if you want to restart immediately after it has stopped. The car keeps a log of how long the engine has been stopped by this function. I find it takes less than 500 km to get to an hour of stop time. My car to date has logged 140 hours - quite a fuel saving.
While it doesn't pretend to be a sports car, the 6 can be enjoyable on a mountain road. It handles the bends well for its style of car, and the torque makes for real enjoyment - I wouldn't go as far as saying thrills.
The infotainment system is the car's weak point, even by comparison with other vehicles available at the time. I believe the new model's version is much improved. I have had little trouble with the voice control, though it is clunky in operating the sat-nav. When I bought the car I had a Nokia phone and I loved the text to voice function. Now I have an iPhone and this function doesn't work. I also play music from an old iPod plugged in in the centre console bin. This mostly works well, but the system doesn't remember what I was listening to last time. When I restart the car, it always plays the same song - the one that's first in the alphabetical listing.
I can thoroughly recommend this car for a small family, and think the driver should particularly enjoy it. Just check it out carefully if you have a tall front seat passenger, like to take lots of luggage, or need to know your text messages instantly.