I like to keep a small amount of soap in my rucksack, largely because I need to have clean hands when handling my contact lenses, but also to keep my pots clean. I have up until now been using Lifeventure All-Purpose Soap, but as I was wandering the isles of our local Tesco I found Ecover's biodegradable washing up liquid. Has anyone had experience of the two and which is the sounder ecological choice when backpacking?