5 good reasons to have it regularly :

1. A quick fully-clothed massage , given on a special ergonomic chair at the medical center.
2. An interesting tool for managing stress and for preventing the RSI (repetitive strain injury).
3. When used regularly, it optimizes quality of life and prevents the appearance of various pathologies due to physical, mental and emotional stress.
4. Since its therapeutic action increases the body’s regenerating capacity, massage is recommanded as an effective means of treating several health problems.
5. Because it generates physiological effects similar to those which are produced by physical activity, massage improves blood and lymph circulation and consequently promotes cell regeneration.

When it comes to more specific problems as lower back or stiff neck problems, the chair is the most appropriate because the position relieves those parts of the body more than on the floor.  

There is a follow-up and the sessions can last longer (40 min). 

As for the therapeutic shiatsu on the floor, the “shiatsu on chair”  is focused on the meridians and acupuncture points (tsubos).
It helps to avoid a lot of health worries (tireness, slow digestion, pains of all kinds).