The best fish I ever ate was a buffalo carp. I was out below the dam of our local reservoir and a couple of my students were out bowfishing. They hit a ton of regular german carp, and one 17lb buffalo that they gave to me. I pressure cooked the giant fillets (with some bones still in) for a few minutes, then flaked off the meat and made fish cakes. They were delicious.
My second favorite fish is bullheads. They're fun to catch and good to eat!
Weirdly, the best fish I ever had was when I was in grad school taking Ichthyology. As you can imagine, seining etc for Educational Material produced a considerable supply of food and on one trip in particular, along the NC coast, we deliberately set up a taste-test at the end of the day. There were like fifteen plus kinds of (ocean and brackishwater) fish, I forget what all. The professor grilled 'em all on a fine-mesh grill on the BBQ. Being an ichthyologist he was a pretty good fish chef <g>
The winner, hands-down? Lizard fish. I'd look up the latin name if I thought anyone cared but it's a total trash fish, normally thrown back in disgust. Looks sort of like a sucker, but with lots of pointy teeth. Bony as all heck, but very thin bones that you can eat. MAN was it ever tasty.
Moral of the story - don't assume that fisherman lore *necessarily* distinguishes correctly between things worth eating and things not worth eating