I prefer using double tapers but then I thorw DT's on single and two handers. In regard to line types I don't think it make a huge difference, as the others have stated the keys here are buuilding a system the minimizes two things: hingeing and sticking i the guides. Throwing DWE on a 7wt can't be much fun. I make braided loop connectors with a small <1/4 inch loop to join sections, the aqua seal the loop. This has worked very well with no issue of hanging or breaking. Customer lines are a labor of love but when you tweak it just right man what a difference.

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