Comparing a couple of rentals I've had recently, the Altima 4-cyl with the CVT got amazing mileage--I really think every automatic transmission will eventually be a CVT--and it had some nice features. I liked the keyless push-button ignition a lot, having never used one before.
But the '12 Honda Accord 4-cyl I rented also got pretty good mileage, and despite the lack of certain features like a CVT for the automatic, and keyless ignition, it felt like the better car. The engine was smoother at low RPM, and I don't know if it was quieter, but it sounded "smoother" at higher RPM.
The Accord's suspension is better, too. That's not to say the Altima was bad, as it normally handled pretty well, and rode smoothly. The difference isn't so apparent at first; I had to become comfortable enough to push each car a little more than normal. That's when I could really tell that the Accord is smoother, quieter, and more secure on the bumpy winter-ravaged roads in my area. Basically, the Accord is less upset when you hit a few bumps on a highway ramp or a curvy road.
I believe the Altima was an '11 (might have been a '12 though), and the Accord was a '12. Both had a little less than 2,000 miles when I drove them.
