I love the idea of this thread.
I think the most underrated fish of all time is the Royal Gramma. Imagine if you never saw it before, and all of a sudden someone discovered it. Given its color an hardiness, it could be a $500 fish! But because they are common and been around forever, they are affordable. I once got one free with purchase of a Yellow Tang! I love me some RG!
Overrated... super-expensive coral with crazy names. Some things you just get what you pay for, no doubt, but just because it has some cool name doesn’t mean it looks worthy of such a name (and price)! I’m into the brewing scene and I tell people all the time, just because you know a place that makes their own beer, that doesn’t mean that it’s good! Same with these coral names. Just because it’s called whatever, doesn’t mean that it’s awesome. Though, I’ll admit, I have a few “brand name” coral - and I’ve also spent money on bad beer! Oh well!