It produces an absolutely lovely, very arty project. Even blades of grass look beautiful, especially when enhanced with the very fine tip pigma pens or some such. Because they are not intended for washing, I simply set the colors with heat. If you think they might be washed, I'd give them a vinegar bath, but you might find some of the colors/natural dyes tend to bleed.
As to the loudness, it's deafening and was hard on my arthritic wrists. I had to go out to my friend's farm far away from disturbing any neighbors and wear ear plugs for my own comfort.
Notwithstanding, it's quite worth it and don't forget to get the kids involved in this. Little boys especially just love making noise and banging on things. Just get away from your neighbors.
Have fun!