BH - I usually do the same thing you do. There will be disagreement from others on the board but I would never use anything but a 2-peice rod for this application.
I broke my Sage steelhead fishing on the Salmon R. about a month ago but it's becuase I grabbed the blank. Lots of times this is the culprit or you might have had a ding in the blank from splitshot/bad cast, etc (might want to be real careful about selecting those blems)
Hate to bash but a good friend has a reddington wayfarer and they are not designed to handle big violent fish like kings - regardless of line wt. He has broken his 5wt a number of times, including the reel seat (go figure)! You could get away with one for stripers/blues but not for kings where you have a limited area in which to fight the fish, heavy current, structure to avoid, etc.
Finally, I would move up to a 9wt with a good fighting butt for GL salmon especially if you plan to release the fish (not play them to death). As Markinetic noted there's no sense in using a tail snare unless you're planning on killing the fish. Better off to get them on their side in an eddy of shallow water to make your move. IMHO a 10ft 8wt is a great steelhead rod but not enough low-end to get a king to the beach.
Sounds like you might just need a little more ammo before going after those big mudsharks.