I've been experimenting with circle hooks for salmon and steelhead for the past couple years. I'm not ready to make any pronouncements but under certain circumstances, they work great. At other times, not so good.

I only use them in rivers with bait (eggs/shrimp). The biggest factor seems to be the type of water you're fishing. The slower, the better with circle hooks. If you're fishing a pool with eggs for Chinook and coho, they're terrific. Slow hookset, great penetration, very few lost fish. In fast water, I can't hook anything with them, particularly steelhead. In fast water, you need a quick hookset, which won't work with circle hooks. A slow lift of the rod is the only way they're effective. But trying to do this in fast water means you're going to loose the hookset.

Give them a try when you're fishing a pool for spring Chinook. They can be very effective.

I will continue to experiment and report back.