I think it's all about what the fish have been eating. Red meated trout will taste great usually due to the crustacean heavy diet, while the whiter meat fish can tend to taste muddy. Catch location also has an impact. Crane Prarie trout are notoriously muddy due, I believe, to their high intake of insects. Also the fatter the fish, the better finished product. It's harder to overcook the fat ones. As a general rule, I have found kokanee and land locked coho to be tops, followed by brookies and browns, then cutties and rainbows, with those issues discussed above coming into play which could make them better or worse than the general rule. A sea-run cutt will be fantastic, while a stocked pond cutt will be suspect. A rainbow with access to crawdads and freshwater shrimp will make your mouth water, while a muddy river/lake insect sucker will make you wish you were thinking catch and release.