Been enjoying hammering shapes on wood so much that i'm really interested in trying to shape pendants perhaps up to 2 inches in length on a sandbag. Notice cookson has one
https://www.cooksongold.com/Jeweller...bag&channel=uk

and also several grit bags which sounds tempting.
https://www.cooksongold.com/Jeweller...bag&channel=uk

Does anyone else use these to shape metal? How do you find working with them?