With the parameters you've set, I think they'd all float long enough to be out of sight by the time they started to sink. However, and just a guess, maybe the quill might last longer because it has a natural resistance to water, then the biot, dubbed body and the first to 'sink' would be the thread body. By the time the fly sank though, the hatch might be over and the trout may be looking for wet flies, lol.

Allan