I find where you catch them makes a big difference - whether or not they are still silver - or have adjusted to the freshwater...
That's why we call them "boots" - no comparison between an ocean fish caught 100+ miles from the river & a boot. The small immature's can taste pretty nasty as well. When I buy Chinook (cheapest way to get it IMO) I ALWAYS look at the skin to make sure it isn't starting to turn & also it has to have a thick belly or else I pass. All the white's Iv'e caught WCVI have been great as have been those Iv'e bought outta Sitka.