Most of my fish purchases that aren't canned (like my beloved kippers) have been decent. Lately the farmed salmon I've been buying (skinless fillets) has been Norwegian salmon. The skin on fillets are from Chile, but I rarely buy those. My steelhead trout comes from Chile and it's quite nice. When I get a wild caught salmon it is inevitably Alaskan. So far I've been quite happy with all of them. Sadly, I have a daughter who just won't eat white fleshed fish. That's sad, as I am big fan of fried catfish!
That is a tragedy.
Some white fleshed fish are delicious; not just the obvious, such as cod, but others, such as monkfish - which is the backbone of much Spanish cuisine - are wonderful as well.