If you try one beauty product this week, make it a dry shampoo that defies all expectations

A marble backdrop with a circular image of a hand with red fingernails holding a white and purple bottle of K18 Airwash Dry Shampoo with lettering below reading sunday service and an image of fiona mckim with blonde hair and a black t shirt on, smiling .

For some types of beauty product, the gap between best in class and bottom of the bargain bin is vast. For others, not so much.

I've spent years thinking that even the best dry shampoo wasn't a million miles away from a 'this'll do' bottle picked up for a few quid in airport Boots. I've tried variations with nicer smells and textures, sure, but ultimately they all do their job in much the same way.