Nothing.
I should mention that I don't own this car, I rented it. Therefore I can't comment on the reliability, but I can comment on performance and comfort.
One thing I noticed immediately is the poor visibility due to large door panels (not sure what they are called, the panels that are between the front and rear doors for example), checking the left blind spot is problematic.
Also, the panels that are on the sides of the windshield block part of the view when turning.
The steering wheel blocks the top part of the speedometer therefore I couldn't see the speed unless I moved up or down a little. (Maybe for people with different height this wouldn't be a problem.)
Someone mentioned in one of the reviews that the seats are uncomfortable. I agree with that, and the headrests make the neck hurt for some reason. Apparently they were bent forward too far, but this is good for safety probably.
The acceleration is adequate, the turn signals are especially convenient when changing lanes.
Braking is quick.
I have to agree with the reviewer - the driver's seat is absolutely horrible in the G5.
GM - test the competition again and build in better lumbar support in the seats.
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