Never eat farmed salmon, much higher levels of bad Omega-6 fats, always try to get wild caught.
The jury is still out on Omega-6. In moderation the consensus is that it is heart healthy. Further, farm raised salmon never has parasites, while wild salmon are always infested with parasites. This is why farm raised salmon is one of the few fish that are safe to eat raw. Wild salmon should never be eaten raw.
As for taste, the farm raised is much superior due to its higher fat content. The finest Scottish lox makers only use farm raised salmon. I make cold smoked lox from farm raised atlantic salmon and imho it is better than the most expensive commercially produced lox.