I bought the large scuttle a couple of weeks ago, before that I was using a cappucino mug.
I find it works great for building lather with creams or with soaps. For creams I use a slightly bigger/softer brush, swirl the brush in the cream then transfer to the scuttle to build the lather. For soaps I use a smaller/stiffer brush, load the brush up on the soap cake until lather starts to form, then transfer to the scuttle to build the lather.
I doesn't work any better/worse than a lathering bowl, just it looks nice in my bathroom and keeps the lather warm. I'm very happy with it. :)