I have it in 7wt (F7WF) and can't only use it for refining my casting but since it's very similar to the steelhead taper (which I have fished hard for years) I would have to say it's a great fishing taper as well.
You have my curiosity though, a 5wt would probably make a superb stillwater and broad river line.
If you fish big weighted streamers I might go to a more compressed taper though.
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