filaments barbs worked well until my trimac got bigger.i know some people have had trouble with SD's being skittish,these 3 have been good in with the salvinis
I am not sure if you are referring too dither fish or dither/target fish. Either way here are my silver dollars. Awful dither fish but great target fish.
Filament Barbs rock! Mine are well over 5" and chunky. My JD hasn't made any attempts at them (though I'd be less confident with an Oscar or, as virgil2090 wrote, a trimac).