I don't, (see above), but those who do use big stimulators
in yellow or orange.

On the big tailwater rivers here in Montana (Missouri, Big Horn) you often
want to fish with small dry flies--that I can't see--especially on
the breezy, overcast days, when the fishing is usually at its best.

So I like to fish an extra-bushy #16 or #18 Pale Morning Dun or even
a Royal Wulff (that I can see) with 24" of tippet behind that (tied to
the bend of the hook)....with a smaller, essentially invisible dryfly at
the end.

So the bobber fly doesn't necessarily have to be a big Stimulator.
Sometimes a #16 PMD accomplishes the same thing. The bobber fly won't
catch as many fish as the itty bitty out at the end of the line.
But it will catch fish, which is something no foam or yarn indicator
has ever accomplished yet.