By far, most vehicles (cars & trucks) in the world came factory-equipped with a twin-tube style shock or strut; probably 85% or more. The twin-tube is cost-effective and performs very well when the vehicle is operated within its designed purpose and for average, every-day use. In many other model vehicles, when the manufacturer designs a vehicle for more than average driving conditions, they often choose a monotube style shock. It's a bit more costly, but has a quicker response rate, has no performance fade due to aeration and can automatically add performance just when needed.
For vehicles factory-equipped with twin-tubes, the monotube replacement shock absorber becomes a performance upgrade opportunity. It can increase a vehicles handling and stability without dramatically decreasing ride comfort.