Thanks everyone
@rozzz. Yeah it is worth getting. You know how difficult is black colour and you have to polish it after every 10 days or at least once a month and wash several times.
The dust will still come to car, but could be cleaned with a wet cloth very easily without leaving any streaks or marks behind.
I still clean my car with wet cloth even the body is dirty after rain. Now tell me is mere wet cloth enough in the case of a normal black car with all the dust and rain drops and mud? That is the advantage.
Plus the pain sealant in RS prolongs the pain life and retains the shine over the years.
