A good line for your suggested uses and flies would be an SA (mastery) "Headstart" in a WF4F. It is about a half lines size heavy with a good bit of the forward mass of the line in the head much like a Bass Bug tapered line. I have found that SA lines in trout sizes for example tend to handle the heat better than RIO in trout sizes. RIO lines are excellent for cold water applications. If you are going to jump up to a 5wt, I have used the SA Supra lines in warmwater applications here in TN, and they held up very well to heat and dirty water. A great buy for $50!

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