That said, they have a bit of a bad rap in beauty. Some believe that they don't lather up or clean hair as well as 'normal' shampoo. Then there's the argument that they are slippery and messy when wet, and no one wants sludge ruining their bathroom shelfie. So I decided to put my hair on the line and try as many solid shampoo bars as I could get my hands on, to whittle down the very best. Here’s how I got on...