This is so much better than the synthetic dusters and will last a lot longer. And it picks up the dust rather than just relocating it.
You need to follow the instructions - swizzle the stick between your fingers to create just enough static to attract the dust (off your keyboard, computer screen etc), hold it out of the window and swizzle again to shake out the dust. Then when it gets dirty, rinse it out in soapy water, and when it is dry, comb it with a pet comb (nice touch!)
As the first reviewer says, put a plastic bag over the head to stop it attracting more dust when not in use. Note: it is not all that mini, around 6" diameter, so if you need to trim it after some wear, there will still be plenty left.
In a nutshell, it does the job perfectly and is very good value.(I got several through Adams Bros who were very nice to deal with).