As previous posting, look around and buy the bits, it seems a high price for that kit. I got my soft nylon brushes and a sponge of the same design from Instore for about £3 each and also a nylon brush for pot washing for cleaning cassettes, chain rings etc and my wheel brush from Tescos for 99p. All in the car section.
Any old sponge and soapy water does the trick. If you're feeling plush get some car shampoo if not a bit of washing up liquid.
Washing up brushes for the cassette and chainrings, old t-shirts for chain and polishing.
Those brushes don't actually last very long either, and muc-off is glorified soapy water.