Synths are great at building a flawless lather every single time. But where's the fun in that? I still enjoy using them but I never have the fun of using other brushes like boars.
I always come back to boar brushes. I find them to be incredibly inconsistent, for example the same model of Omega boar brush will different batch numbers, some might be stiff and pokey and another will be soft and floppy. I really enjoy the inconsistency, there's an element of pot luck to it.
I tried a few badger brushes and despised them, I sometimes think I'm missing out on them, but I'm happy with my collection of synths and boar brushes.