What type of vacuum cleaner performs best on a carpet? AN UPRIGHT!
This is because, in addition to airflow, it also has a brush/beat action.
For upholstery a similar principal applies. Since fine dust will penetrate through upholstery fabrics and that fabric also acts as a filter when you attempt to remove it, the airflow of the vacuum cleaner requires a little assistance in the removal of this penetrated soil. Think of it like a flour sieve - if you fill the sieve with flour and wait for gravity alone to pull the flour through, you will have a long wait! However if you assist by tapping the side of the sieve, the flour starts to flow.
A small hand-held, though having less airflow than the vacuum cleaners mentioned, will remove more soil due to the beating action of its' brushes.
An alternative is to use a turbo-head attached to a carpet vacuum. I go a stage further when cleaning mattresses and very dusty upholstery by using an electrically-powered brush-head (own build) and a dust-downer attached to a powerful HWE machine which provides 326cfm of airflow. Being located outside the building, the exhausted air does not compromise IAQ - ideal for allergen treatments.