Very nice job - my CFC takes about the same time for the volume you're talking about, though.
I'd say a major benefit of this is not having wort /inside/ the chiller - which is fine with a plate chiller, but in a CFC I'm always a little more concerned about sanitation.
I'm still not sure there's a clear winner re: plate/cfc/immersion, but clearly immersion works best with a whirlpool.