If you do small batch reloading and don't care about shiny brass the sonic cleaner will probably work well for you, oh and they are dust free. You will have to tumble the brass to get them shiny though after they dry.
My understanding how they work is the ultra sonic waves create tiny bubbles that act as scrubbers that move the solution into the tiny crevices, scratches, etc.
My tumbler is in the garage so I don't care about the dust or noise. Dump the brass in and go do something else. Let it run three hours, nice and clean and shiny. There are several Youtube videos with sonic cleaners being used. You have to be interactive with them, move the brass in and out and typically they require several cycles to get the brass clean.
Unless you bake the brass to dry I don't think the sonic cleaner will be any faster. Actually it will take a lot longer if you have to leave the brass to dry overnight or out in the sun for a few hours.
But I do think they will work great for some people, just depends on your situation.