Exterior styling
Imposing, it makes the car look solid.
Powertrain performance
Its smooth power delivery, with an adequate amount of torque. Engine is coupled to a responsive 5-speed automatic, which shifts seamlessly.
Front seat support & comfort
These are the best seats to ever have been in a car, period. And they have seat heaters, too--which is awesome.
Reliability & durability
The non-turbocharged engine in this car will last forever, with the right maintenance and upkeep. The car only needs to see the dealership once every 7,500 miles, which is nice, and services are not overly expensive.
Safety & braking
The S60 feels extremely rigid and safe, and I feel very well protected in it. The car handles and stops with great confidence.
Rear seat room & comfort
Rear seat room is lacking. Yes, three people will fit, but they won't be very comfortable. Also, if the driver is tall, it's hard to fit anyone in the rear seat behind the driver at all.
Audio & nav systems
The audio system isn't the greatest; the radio is fine (but lacks in inputs), but the speakers are pretty terrible in the basic audio configuration. Also, since the radio is integrated with the dashboard and other electronics in the car, it is difficult to replace it with something better. And even if you would be able to, an aftermarket radio would look completely out of place.