I have a dune color Outback. It has a sort of "speckled" finish to it that makes the crud a bit less noticeable. On the other hand that finish means that even freshly scrubbed it never really seems "clean" to me. I scrubbed all my kayaks down at the end of November and there was a marked difference before and after, but the Outback wasn't "ooh, shiny" like the others even with the UV protectant applied.
Not that it bothers me - it's already getting grungy again!
I'd probably go with the dune again if I was buying an Outback or Revo since I spend a lot of time up creeks and rivers, and along muddy shorelines (about all we have in Oklahoma). My Tandem Island will be yellow, though, for visibility out in the middle of the lakes. (And as you say the black fittings look great with it!

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