I just got done rubbing my bumper out. It looks pretty good in that it now doesn't look out of place on my car.
Be gentle. Practice on a non-visible area like under the nose first. Don't use a heavy hand or rub too long. Just enough to bust the gloss.
I haven't seen it in direct sunlight yet because I'm still re-assembling the grill, but I don't see any swirl marks in indirect sunlight, under the fluorescents or using my drop light reflecting on it.
It was pretty funny seeing the reaction I got from body & paint guys when I asked them how to dull my shiny new paint job. Nobody had ever asked them that question before and they just couldn't comprehend it. It was a younger hot rod guy who laughed and understood exactly what I was after. He was the one who, after talking about several options including spray on de-glosser, suggested trying rubbing compound first.
Next step in making my car reasonably presentable is touching up all the dings. The man who did the bumper gave me some of the paint and I have gone around doing all the chips & dings--well, the worst of them-- but it is a flat paint. I think I'll try clear nail polish to seal and even out the bigger ones. We'll see how that works.....Hey, it's already down to a 20 foot paint job instead of 50 foot!
Kill the Buddha