Depends, I use them all plus some other spoons, I like to "match the hatch". I'll use 5.0s when bait is scattered or when I can identify it as herring, I'll use the 3.5 or even better the coho killer when the bait is candlefish. Also, for terminal kings that are starting to get zipperlip-itis I'll go to the smaller sizes.
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The fishing was GREAT! The catching could have used some improvement however........