The Volvo has a three channel system -sensors on both front wheels and one for the rear axle. The system monitors the wheel rotations and checks that all are the same in normal driving. If it sees a small variation, like a tire that is bigger than the rest, it will put on the trouble light. That's whats happened in the Explorer perhaps. As long as the tires are all the same size the system is happy. Four Virgos with the same diameter tires will be no problem.
ABS doesn't make the car stop shorter. It allows you to steer in poor traction conditions while braking at maximum. In gravel and snow ABS will increase stopping distances.
Its a waste of money and complexity having it.