There is a lot of marketing in that also, it lights up a led, that is it, there is no chromatograph or junk dust detector in that suction cup. Keep in mind that the filter must be changed also and also the brush, after some time, and Dyson does not sell them cheap af at all. But you must be rich !
You need to, because 5 minutes later it looks just as dusty.
That laser is extremely good at spotting the smallest amount of dust. Every time you do the floor you'd think it hadn't been done in weeks.