The princely sum of £16.99 might sound like a lot of wonga for a bucket of cleaner, but you get a litre of the normal Less Gnarl wash, plus a litre of concentrated Super Gnarl solution which you can dilute 10:1 to make the normal wash, or use concentrated as a degreaser.
So you get loads of cleaning for your money. The liquid spreads well too, and bubbles away at the dirt on the bike, washing it off most of the time without the need for a brush.
Even the normal diluted solution did a great job at getting the drivetrain gleaming. The strong smell and slippery texture might put you off, but on the whole it's a pretty good cleaning option.