Many cleaners love using this tool when cleaning, specially when it comes to dusting. There are many feather dusters availible and quality of the duster is of course different.
However the best one in opinium is the osthrich feather duster. It is very effective to get dust for example behind computers and thoose places that are not conviniante to reach with microfiber clothes. It can be very timesaving to use the feather duster.
It is very important to not overuse the duster, it will of obviously get full of dust very quicky so it need frequent cleaning. It is best to clean it after every use.

My advise about the feather duster is simple. Don´t overuse it and never forget that is does not come instead of microfiber clothes, it will simply not do the same job.